Answer:
Saudi Arabia
Mecca, Arabic Makkah, ancient Bakkah, city, western Saudi Arabia, located in the Ṣirāt Mountains, inland from the Red Sea coast. It is the holiest of Muslim cities.
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The right reference that you would use to find out more about the location of the river Cosumnes River is an atlas. The correct answer is option A. At atlas is a book that contains illustrations of charts and maps of various parts of the Earth. The word "Atlas" comes from the name of a Greek god "Atlas" who is known to be a Titan who supported and carried the Earth on his shoulders.