The probability that a student 'A' succeeds in a test is 0.85 and the probability that 'B' succeeds in the same test is 0.75. Then the probability that exactly one of them succeeds in that test is

A

$$\frac{13}{20}$$

B

$$\frac{13}{80}$$

C

$$\frac{13}{40}$$

D

$$\frac{17}{40}$$