Questions: Which of the following allowed for heavy casualties during World War I? (1 point) machine guns use of the horse cavalry introduction of the pistol ban on chemical warfare

The answer is machine guns.

Machine guns were a significant factor in the high number of casualties during World War I. They had the capability to fire hundreds of rounds per minute, making them extremely effective in trench warfare. The defensive power of machine guns made it difficult for attacking forces to advance, leading to massive losses.

While horse cavalry was used in World War I, it was not a major factor in the high casualty rates. The nature of trench warfare and the advent of modern weaponry rendered traditional cavalry charges largely ineffective and obsolete.

The pistol was not a primary weapon in World War I and did not contribute significantly to the high casualty rates. Pistols were typically used by officers and in close combat situations, but they did not have the same impact as machine guns or artillery.

There was no ban on chemical warfare during World War I; in fact, chemical weapons were used extensively. However, the question asks about what allowed for heavy casualties, and the ban on chemical warfare would not be relevant in this context.