Answer:
D: product
Step-by-step explanation:
All I remember is that the answer to a division problem is quotient and multiplication is a product. Hope this helps :)
On the unit circle: the end of the terminal side of a 90 degree angle is (1,0) where 1 is the value of sin(90°) and 0 is the value of cos(90°)
On the graph of sine: 90° =

radians. if f(x) = sin(x) in radians, f(

) = 1/2