The largest religious groups in Southwest Asia are Sunni and Shiite Islam, followed by various forms of Christianity and Judaism. There are smaller minority religions like: Baha'i, Druze, Yezidi, Yarsan, Shabaki, Mandaean, and Alevi.
People in Southwest Asia do not eat different foods on account of religious differences, but rather based on regional differences. The one exception is that some Christians eat pork whereas religious Jews and Muslims do not, but these are few and far between since pork is hard to find outside of Israel in Southwest Asia.
Nothing. If by "the religions of Southwest Asia" you are referring exclusively to the three monotheisms (Judaism, Christianity, and Islam), then the unifying trait is monotheism. However, there are numerous religions from Southwest Asia such as Zoroastrianism and Mandaeism whose adherents are henotheists or polytheists.
judaism
Hinduism, Buddhism, and Islam
Christianity and Judaism
some religions include Islam, Hinduism, Catholicity, and Christianity depending on the country
It's Jerusalem. It's very important to the Jewish, Christian, and Muslim religions.
Southwest Asia in general, they were in different parts of it but close enough together to be "The Birthplace of Three Religions"
Islam,Christianity,and Judaism
Judaism, Christianity, and Islam.
Judaism, Christianity, and Islam were all founded in southwest Asia, more specifically the Middle East.