Why do so few plants grow on the rainforest floor?

The floor of the rainforest is some of the most fertile soil everywhere but you can't plant crops on the rainforest floor. This is because there's no sunlight. Even though it's massively fertile, you can't plant crops there or at least a lot of crops because there is not enough sunlight.

the answer is b.) hydrogen bonds between bases.

sex cells are usually half's then they find another half and make a fertilize egg