The correct answer is (a) 7 years.
According to Islamic law, a Muslim woman can seek divorce if her husband is not traceable for a period of 7 years. This is known as “talaq al-ba’in” or “irrevocable divorce.” The woman must first wait for 3 years after the husband’s disappearance before she can file for divorce. If the husband is still not found after 3 years, the woman can then file for divorce and the court will grant her a divorce.
The reason for this rule is that it is considered to be a form of protection for women. If a husband is not traceable for a period of 7 years, it is likely that he has abandoned his wife. In this case, the wife is entitled to a divorce so that she can remarry and start a new life.
The other options are incorrect because they are not the correct length of time that a Muslim woman must wait before she can seek divorce if her husband is not traceable.