This question seems to be incomplete. However, there is enough information to find the right answer.
Answer: B. "At the time, he was trying to explain several conditions that puzzled him."
Step-by-step explanation:
Option B states that Lovelock was trying to find an answer to many conditions that "puzzled" him, which implies that he was trying to solve a mystery.
Option A is not correct because it only states who and what James Lovelock did, without any references to his intentions.
Option C is also incorrect because it refers to the impressions others had about the subject. And option D won´t answer the question either, because it describes the theory, not what led to its development.