I think A). Adjective
Answer:
A diamante poem is a poem in which seven lines are formed to appear in the shape of a diamond.
Explanation:
Diamante poems are split into a structure of lines rather than words. They have an odd and strict structure.
1. Noun/subject
2. Two adjectives that describe the noun/subject
3. Words that end with -ing that describe the noun/subject
4. Two words about the first noun/subject and another two words about the antonym/synonym
5. Three -ing words about the antonym/synonym
6. Two adjectives that describe the antonym/synonym
Antonym/synonym of the subject/noun
Here is an example from one of the founders of Shadow Poetry, Marie Summers: