A major focus of modern evolutionary ecology is the study of

3. The primary purpose of the passage is to

Explanation

A. This option is not the primary purpose of the passage. While the passage mentions that Heliconius butterflies lay their eggs on Passiflora vines, the main focus is not on explaining why they do so. Instead, the passage explores the broader coevolutionary relationship between these butterflies and Passiflora vines.

B. This option is not the primary purpose of the passage either. While the passage does touch on how Heliconius butterflies use factors like leaf shape to select host plants, it does not extensively describe the manner in which they distinguish Passiflora vines from other plants. The primary focus is on the coevolutionary dynamics between the two species.

C. This is the correct answer. The passage is primarily focused on exploring various aspects of the coevolutionary relationship between Passiflora vines and Heliconius butterflies. It discusses how their interactions have led to the evolution of specific traits and adaptations in both species.

D. This option is not the primary purpose of the passage. While the passage does use the relationship between Heliconius butterflies and Passiflora vines as an example of coevolution, it does not aim to provide an overview of coevolutionary relationships in general. The main focus is on the specific interaction between these two species.

E. This option is not the primary purpose of the passage. The passage does discuss how Passiflora vines have developed defenses against Heliconius butterflies, but it does not make an argument that only the adapted species of vines survive. Instead, it focuses on illustrating the ongoing coevolutionary dynamics between the two species.

In summary, the primary purpose of the passage is to explore various aspects of the coevolutionary relationship between Passiflora vines and Heliconius butterflies, making option C the correct answer.

Answer: C