During Middle Adulthood,which of the Following Best Explains Why Skin

During middle adulthood,which of the following best explains why skin begins to wrinkle and becomes saggy?

A) Skin begins to lose its fat content and the three layers of skin begin to adhere to each other less firmly.
B) The body retains less water; therefore,skin begins to wrinkle and becomes less pliable.
C) White blood cells begin to decrease in number and skin cells are indirectly affected.
D) The nuclei of skin cells begin to shrink,which in turn affects skin elasticity.