Correct answer: A

The correct answer is A species with an unusually large effect on ecosystem structure relative to its abundance.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: Removing a keystone species can cause substantial food-web or habitat changes even if the species is not abundant.
3. Connect evidence to impact: The correct answer is A species with an unusually large effect on ecosystem structure relative to its abundance.

Correct answer: B

The correct answer is A connected habitat pathway that allows organisms to move between separated areas.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: Corridors can maintain gene flow, seasonal movement, and access to food or breeding sites.
3. Connect evidence to impact: The correct answer is A connected habitat pathway that allows organisms to move between separated areas.

Correct answer: C

The correct answer is Species within their natural habitats.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: In situ conservation protects species and ecological processes where they naturally occur.
3. Connect evidence to impact: The correct answer is Species within their natural habitats.

Correct answer: D

The correct answer is The process of assisting the recovery of a damaged ecosystem.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: Restoration can remove stressors, reestablish native species, improve habitat, and restore ecological functions.
3. Connect evidence to impact: The correct answer is The process of assisting the recovery of a damaged ecosystem.

Correct answer: A

The correct answer is Changes in conditions and species interactions at the boundary between habitats.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: Edges can have different light, temperature, wind, predators, and invasive-species pressures than habitat interiors.
3. Connect evidence to impact: The correct answer is Changes in conditions and species interactions at the boundary between habitats.

Correct answer: B

The correct answer is It increases the potential for populations to adapt to disease and environmental change.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: Genetic variation provides the raw material for adaptation and can reduce risks from inbreeding.
3. Connect evidence to impact: The correct answer is It increases the potential for populations to adapt to disease and environmental change.

Correct answer: C

The correct answer is To conserve biodiversity, habitats, ecological processes, or cultural resources.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: Protected areas can restrict harmful activities while supporting conservation, research, and responsible use.
3. Connect evidence to impact: The correct answer is To conserve biodiversity, habitats, ecological processes, or cultural resources.

Correct answer: D

The correct answer is Replanting trees on land where forests were previously removed or degraded.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: Reforestation can restore habitat, carbon storage, soil protection, and water-cycle functions when planned appropriately.
3. Connect evidence to impact: The correct answer is Replanting trees on land where forests were previously removed or degraded.

Correct answer: A

The correct answer is A defined ocean or coastal region managed to conserve ecosystems or species.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: Marine protected areas use management rules that may restrict fishing, construction, extraction, or other activities.
3. Connect evidence to impact: The correct answer is A defined ocean or coastal region managed to conserve ecosystems or species.

Correct answer: B

The correct answer is They transfer pollen and support reproduction of many flowering plants and crops.

1. Identify the environmental science concept: Determine whether the question concerns ecosystems, cycles, populations, pollution, climate, resources, conservation, policy, or environmental health.
2. Apply the systems principle: Bees, butterflies, birds, bats, and other pollinators help fertilize flowers and support plant diversity and agriculture.
3. Connect evidence to impact: The correct answer is They transfer pollen and support reproduction of many flowering plants and crops.