Final answer:
Protecting plant and animal species in a national park is an example of an effort to conserve biodiversity, which is key in preserving ecosystem balance and diversity of life on Earth.
Step-by-step explanation:
Conservation of biodiversity encompasses various strategies to protect and preserve the variety of life forms on Earth at the genetic, species, and ecosystem levels. Among the options provided, protecting plant and animal species in a national park is an example of an effort to conserve biodiversity. This approach helps ensure the preservation of diverse species and their habitats, which is essential for maintaining the balance of ecosystems and the services they provide to humanity.
On the other hand, options such as the use of pesticides and driving large vehicles can contribute to habitat degradation and pollution, negatively impacting biodiversity. Taking a piece of coral as a souvenir after a scuba dive is also harmful to marine ecosystems and therefore counterproductive to conservation efforts. Hence, the correct answer to the student's question is c. Protecting plant and animal species in a national park.