Why has conflict over the control of the city of Jerusalem occurred throughout history?

A.
The city has holy sites that are important to multiple religions.
B.
The city is home to important mineral resources.
C.
The city is on the coast and has a natural deep-water port.
D.
The city is home to dozens of ethnic groups who have fought for control.

Please select the best answer from the choices provided.

A. The city has holy sites that are important to multiple religions.