What do Muslims do on a hajj?
A. They fast during the day for a month.
B. They give wealth to the poor and needy.
C. They pray five times each day.
D. They travel to the holy city of Mecca.

D. They travel to the holy city of Mecca.

Explanation:

The Hajj is an Islamic pilgrimage to Mecca, their holy city. Hajj literally means "to set out for a place,"  or "to attend a journey." For all muslims, it is mandatory for them to have made the journey at least once during their life.

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