What is the age of religious responsibility (Taklif) for a boy and a girl?

Answer

In the name of Allah, divine obligations, including prayer, become obligatory when the signs of Taklif are established. For a boy, this is either completing fifteen lunar years, the appearance of coarse pubic hair (not fine hair), or the occurrence of nocturnal emission (ejaculation); any one of these signs suffices for reaching puberty. For a girl, it is completing nine lunar years, the appearance of pubic hair, the occurrence of nocturnal emission, or the onset of menstruation; the occurrence of any one of these signs is sufficient for her to reach puberty. Allah knows best.