Given that r < 0

Lets take two cases
Case 1: r = -1
Case 2: r = -2

Case 1: r = -1
Quantity A = 45r = 45 * -1 = -45
Quantity B = \(\frac{45}{r}\) = \(\frac{45}{-1}\) = -45
=> Quantity A = Quantity B

Case 2: r = -2
Quantity A = 45r = 45 * -2 = -90
Quantity B = \(\frac{45}{r}\) = \(\frac{45}{-2}\) = -22.5
=> Quantity B > Quantity A

Clearly, We cannot say which Quantity is greater as they can be equal or unequal too.

So, Answer will be D
Hope it helps!