Suppose That More Police and Security Workers Become Aware That

Suppose that more police and security workers become aware that wearing bulletproof vests can protect them from injury and decide to start wearing bulletproof vests.At the same time, the price of ceramics used to produce the vests falls.The equilibrium relative price of bulletproof vests
________ and the equilibrium quantity produced _.
A.increases; increases
B.decreases; decreases
C.probably changes, but in an ambiguous direction; probably changes, but in an ambiguous direction
D.probably changes, but in an ambiguous direction; increases