Pineapples, unlike most other fruit, contain an enzyme called bromelain, that breaks up the gelatin into it's amino acid building blocks. [Enzymes are biomolecules that catalyze chemical reactions; most of them are proteins themselves.] Due to the bromelain, your jello doesn't become (or stay) solid.
Answer:
amylin, calcitonin, gastrin
Explanation:
There are a few for you.
The answer should be C, hope this helps