Study the given paragraph and answer the questions.The sperm has a head which bears acrosome. It helps the sperm in penetrating into ovum. In the middle of the head male nucleus is present. It fuses with the female nucleus. Head and middle piece are attached by neck. Mitochondria of middle piece produce energy for the movement of the sperm. The tail propels the sperm. The fluids secreted from seminal vesicles, prostate gland and cowper's gland collectively called seminal plasma. The seminal plasma along with sperm is called semen. The sending out of semen from male's body is called ejaculation. From normal fertility 60% of sperm should have normal shape and size. And 40% of them must have vigorous motility. Men produce sperm, from the age of about 13 or 14 years, and can go on doing so most of their lives, although their power to do so decreases as they grow older.(A) The term that we use to describe a sperm cell fusing with an egg cell.(B) Which part of the male reproductive system (human) produces the sperm cells ? (C) How does the sperm break through the egg cell membrane ? (D) What provides energy for the movement of the sperm ?