Capacitation refers to changes in the 

• Sperm before fertilization

• Ovum before fertilization

• Ovum after fertilization

• Ovum after fertilization

A.

Sperm before fertilization

Capacitation refers to activation of sperm cells before fertilisation. It involves reorganisation of molecules in the outer membrane of sperm head.
Capacitated sperm releases enzymes from their acrosomes to penetrate the cells and zona pellucida surrounding the egg.