Does touching one's private parts (genitals) or anus with the palm or back of the hand nullify ablution?

The answer to the issues of ablution being invalidated by touching the private parts is as follows:

1. Touching with other than the palm: Ablution is not invalidated by touching with other than the palm, such as touching with the forearm or elbow. This is the view of the majority of scholars. 2. Touching with the inner and outer part of the palm: The Shafi'is held that ablution is only invalidated by touching with the inner part of the palm, relying on the word "أفضى" (afḍā - reached) in the noble Hadith. The Hanbalis held that touching with both the inner and outer part of the palm invalidates ablution, relying on the general term "اليد" (al-yad - hand) in the Hadith. The more authoritative view is that of the Hanbalis, that touching with both the inner and outer part of the palm invalidates ablution. 3. Touching the anus: Scholars differed on whether touching the anus invalidates ablution: The Shafi'is and one narration from Ahmad held that it invalidates ablution. Malik, Abu Hanifa, and the other narration from Ahmad held that it does not invalidate ablution. The more authoritative view is that it does not invalidate ablution, but the door of precaution is open.