PLEASE HELP ME!!!!
Which best describes the reason for the use of trench warfare in World War I?

A. Soldiers dug into the ground in order to protect themselves from the harsh weather.
B. The soldiers needed a large space in which to bury all of their deceased comrades.
C. Soldiers dug into the ground to protect themselves from machine gun and mortar fire.
D. The soldiers wanted a clear line from which to launch their offensive attacks on the enemy.