Explain how Abraham creates a unified link between Judaism, Christianity, and Islam

The Abrahamic religions, also referred to collectively as Abrahamism, are a group of Semitic-originated religions that claim descent from the Judaism of the ancient Israelites and the worship of the God of Abraham. The Abrahamic religions are monotheistic, with the term deriving from the patriarch Abraham (a major figure described both in the Tanakh and the Quran, recognized by Jews, Christians, Muslims, and others).[2] The three Abrahamic religions trace their origins to both sons of Abraham. For Jews and Christians it is his youngest son Isaac and for Muslims, his eldest Ishmael.

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ok sorry the answer is a. by their religion