What effect did the controversial and inconclusive nature of the war have on the military personnel who served in vietnam?

 The men who served in Vietnam War witnessed violence and loss of their co-military and friends. The men in Vietnam War were younger than those who fought for World War I and II. Many died during the war and got injured. Some men did not suffer any impairment or physical injuries, however, they suffered stress-related impairment known as Post-Traumatic Stress Disorder. This condition is a reaction from violent traumas from the war. 

The answer is a c b d a c b d