Answer:
A. monotrophic
Explanation:
The latin word for only one is "mono" and it is used in different languages as "mono", in english is used to express One, only one, and single, in this case if you want to form a word that expresses requiring only one type of food, you would use the pre-fix mono, and the greek root for feed, which is troph, so the word would be mono-troph, or monotrophic.
