Concept:Some Muslims are permanently excused from fasting when they are physically unable to fast, such as the aged and the chronically ill.
Explanation:Fasting in Ramadan is obligatory for every able Muslim.
However, Allah has excused certain people from fasting when fasting becomes harmful or impossible.
Old age brings weakness, terminal illness, and loss of mental faculties.
For such elderly people, fasting is not required at the cost of their health, and this exemption is permanent.
Pregnancy, breastfeeding, and menstruation are temporary conditions.
Women in these situations are excused temporarily, but they must make up the missed fasts later.
Therefore, old age is the condition that causes a permanent exemption.
Answer:B. old age