giant tortoises’ genes to compare the common genetic links among other long-living animals — such as naked mole rats, bats, some species of whales and humans. They found a set of genetic adaptations related to cancer suppression, DNA repair and inflammation, laying the groundwork for future experiments into the mechanics of aging. With the new insight into turtle biology, the researchers also hope this analysis might help prevent the long, lonely end of the world’s remaining giant tortoises.

Question

Use the article excerpt to answer the question. Which sentence from later in the text best helps develop the idea expressed in paragraph 2?
A. Their long, slow existence “has been key to their survival — from a time of overexploitation to a time of greater enlightenment and conservation,” she wrote in an email.
B. Lonesome George was a conservation icon, Caccone said, but a conservation icon that can also provide insights into human health and aging.
C. Thanks to this analysis, the researchers were able to narrow down their original list of 3,000 genes to 43 specific sequences that might have contributed to Lonesome George’s long, disease-free life.
D. By targeting more than 3,000 genes of interest, the researchers could tease out the variations between humans and tortoises.

Answer 1

The sentence that best helps develop the idea expressed in paragraph 2 is:

C. Thanks to this analysis, the researchers were able to narrow down their original list of 3,000 genes to 43 specific sequences that might have contributed to Lonesome George’s long, disease-free life.

This sentence elaborates on the researchers' findings about the giant tortoises' genetics and relates directly to the efforts to understand the mechanisms of aging and health, which aligns with the focus of paragraph 2.