Explanation:
The theme is the message of the story or poem. Since you didn't put the actual poem in the question, I'll go over each answer to see which one is right.
A: If this is the right answer, then the poem would be about people not being grateful for nature until they final learn to take pleasure in it.
B: The poem would be about being a part of nature.
C: The poem would be about how nature changes and nothing stays the same forever.
D: The poem would be about how cherry trees are very beautiful in spring, but not so much in other seasons.
The correct theme should reflect on what the poem is trying to teach you.
