Name the most important hormone which causes the uterine contraction strongly.

The correct option is A Oxytocin
The act of expelling the full term foetus from the mother’s uterus at the end of gestation period is called parturition. It is induced by a complex neuroendocrine mechanism. Parturition signals originate from the fully developed foetus and the palcenta, which induces mild uterine contractions called foetus ejection reflex. This triggers the release of oxytocin from the maternal pituitary. Oxytocin induces stronger uterine muscle contractions.