Question

this photograph shows a military tactic of

trench warfare

bombings

flamethrower
source: library of congress, prints and photographs division

Explanation:

The photograph shows soldiers in trenches, a key feature of trench warfare used in World War I. Bombings involve aerial or artillery attacks (not visible here), and flamethrowers are a weapon, not a tactic shown by the trench setup. So the correct tactic is trench warfare.

Answer:

A. Trench warfare