waxy coating on the stem green pigment in the cells sharp spines as the leaves long roots near the surface
I gave my students this multiple choice question: Which structure best protects a cactus from being eaten by animals?

Only one answer is correct among these 4 choices:
- waxy coating on the stem
- green pigment in the cells
- sharp spines as the leaves
- long roots near the surface

Could you tell me which one is correct?

sharp spines as the leaves