What do all volcanoes do? A. destroy land
B. erupt violently
C. stay dormant
D. build land

D

Explanation:

when they cool over it creates new land

Trench warfare most likely led to stalemates during World War I by making it "difficult to gain an advantage".

Trench warfare is a kind of land fighting utilizing occupied battling lines comprising generally of military trenches, in which troops are very much shielded from the adversary's small arms and are generously protected from mounted guns. The most well-known utilization of trench fighting is the Western Front in World War I. Trench warfare happened when a revolution in firepower was not matched by comparable advances in portability, bringing about a tiring type of fighting in which the defendant held the favorable position.