Read the following statements and choose the correct option.

a. Soon after the infant is delivered; the placenta is also expelled out of the uterus.

b. Parturition is induced by a complex neuroendocrine mechanism.

c. The milk produced during the initial few days of lactation is called colostrum.

d. During parturition, oxytocin acts on the ovarian muscles and causes stronger uterine contraction.

Which of the above are correct statements:-