When muslims bow toward mecca, the holy city of islam, five times a day at fixed times to pray to god, and christians participate in the celebration of communion to commemorate the life, death, and resurrection of jesus, they are engaging in: ?

The correct answer is rituals. 

Rituals refer to religious ceremonies and practices performed by people belonging to a religion at specific prescribed times or sequences. For instance, Christians celebrate Christmas and Easter at certain prescribed times of the year, where they celebrate the birth and Resurrection of Jesus Christ. Similarly, Muslims chant certain prayers, fast and bow a fixed number of times at prescribed times of the day.