Are the source of antibody-producing cells.
a. b cells
b. macrophages
c. plasma cells
d. t cells
e. monocytes

Option C. "Plasma cells"

Explanation:

An antibody can be defined as a protein produced by the plasma cells which are utilize by immune system able to bind with specific antigen that protects body from diseases.

Plasma cells are antibody-producing cell that originates from B cell. The antibody produced from plasma cells are released into body and lymph, these antibody molecules bind to the target antigen and allow destruction or neutralization.

Hence, the correct option is C.

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.