Events that damage the cell's regulatory apparatus can cause the uncontrolled division of cells called a) cancer. b) hyperplasia. c) mutation. d) phosphorylation.

Option A, cancer

Explanation:

In cancer, cells with in an organism start dividing and there is no mechanism to stop their division thus an unstoppable cell division takes place in cancer.  

All the cells with in the body have a certain life period and at later stage of its life it gets instruction to die and stop dividing/reproducing. But in case of a cell affected by cancer, this regulatory mechanism fails and thus the cell enters into a phase of unrestricted cell division.  

1. dermis

2. chemical

3. urine

4. viruses

5. antibodies

i think the answer is a.keratin is the pigment responsible for skin color.