This fatwa is based on a hadith reported by Hazrat Muhajir bin Qunfudh. He said that he greeted the Prophet Muhammad peace be upon him while the Prophet was relieving himself, and the Prophet did not reply until he performed wudu and then returned the greeting. From this hadith, Islamic scholars explain that greeting a person who is performing wudu is not disliked. It is also not disliked for the person doing wudu to reply to the greeting. Both greeting and replying are permissible according to the Islamic ruling. However, it is better and more appropriate to reply after completing wudu. This opinion is mentioned by Islamic scholars in classical fiqh books and is supported by the fatwa references provided.