Assertion: Menstrual cycle starts only after attaining sexual maturation (puberty).
Reason: The first menstruation begins at puberty and is called menopause.

Assertion is true but the reason is false .

The correct answer is Option (4) : Assertion is true but the reason is false .

Assertion: Menstrual cycle starts only after attaining sexual maturation (puberty). This assertion is generally correct. The menstrual cycle typically begins with the onset of puberty, which is characterized by various physical and hormonal changes, including the onset of menstrual periods in females. Puberty marks the maturation of the reproductive system and the initiation of the menstrual cycle in girls.

Reason: The first menstruation begins at puberty and is called menopause. This is wrong.The reproductive cycle in the female primates (e.g. monkeys, apes and human beings) is called menstrual cycle. The first menstruation begins at puberty and is called menarche. In human females, menstruation is repeated at an average interval of about 28/29 days, and the cycle of events starting from one menstruation till the next one is called the menstrual cycle.In human beings, menstrual cycles ceases around 50 years of age; that is termed as menopause.