Read the paragraph from the hot zone. at six-thirty, he gave an order to move out, and the column of vehicles left fort detrick's main gate and headed south, toward the potomac river. it consisted of a line of ordinary automobiles—the officers' family cars, with the officers inside wearing civilian clothes, looking like commuters. the line of cars followed behind two unmarked military vehicles. one was a supply van and the other was a snow-white ambulance. it was an unmarked level 4 biocontainment ambulance. inside it there were an army medical-evacuation team and a biocontainment pod known as a bubble stretcher. this was a combat medical stretcher enclosed by a biocontainment bubble made of clear plastic. if someone was bitten by a monkey, he would go into the bubble, and from there he would be transferred to the slammer. the supply van was a white unmarked refrigerator truck. this was to hold dead monkeys and tubes of blood.

what is the author’s purpose for including this paragraph?

a: to the reader visualize the thorough precautions that were in place

b: to persuade the reader that safety precautions should always be followed

c: to inform the reader of what could happen if precautions were overlooked

d: to explain in great detail why such precautions were needed for the situation