The answer is: D)The poem suggests that attempts to grasp the natural world through science are useless.
In Walt Whitman’s poem "When I Heard the Learn'd Astronomer" the speaker sits to heard a lecture about an astronomer, at the end of it everyone applauses except he, he only feel sick and tired and suddenly he saw the sky and is there when he understands the magic of the sky not in the lecture but through the experience.