Mansa Musa was the ruler of [___]. He was a devout Muslim, and he took a journey - called a hajj - to the city of [___]. All Muslims are required to make the hajj [___]. The hajj is one of the [___] Pillars of Islam.

Mansa Musa ruled the Mali Empire, and his hajj was a pilgrimage to Mecca. Muslims are required to make the hajj once in their lifetime if they are able, so the correct choice is “once in their lifetime.” The hajj is one of the Five Pillars of Islam.

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