Answer:
B. the uneven meter in the lines and enjambment
Explanation:
There are two ideas to this question, one which answer choices are structural elements and two which answer choices interpret that the rain is a powerful force.
A.the trochees and the iambic pentameter
The poem includes different types of meters.
B.the uneven meter in the lines and enjambment
The poem includes irregular meter because beats do not evenly divide into groups. The pauses that go beyond the lines, enjambment, describe the rain.
C.the onomatopoeia and the couplet
The rain is used to create a vivid image of the storm, but onomatopoeia is sound not a structural element.
D.the alternating rhyme and the meter
The meter in the poem is uneven through out.
E.the dactyls and the half-rhymes
I cannot find half-rhymes in this poem.