The correct option is B related to absence of menstrual cycle
Lactational amenorrhea is the absence of menstruation where ovulation and menstrual cycle do not occur during the period of intense lactation following parturition. It is a natural/traditional method of contraception that does not involve the usage of any device, drug or barrier. It is not a permanent method of contraception, but is only effective for around six months post delivery (when the mother breast feeds the child). The chances of conception are very low during this period because of the absence of ovulation. But there is a possibility of failure of this method.