Let a, b, and c be three distinct one-digit numbers. What is the maximum value of the sum of the roots of the equation (x-a)(x-b)+(x-b)(x-c)=0 ?

**Answer Choices**

A. 15

B. 15.5

C. 16

D. 16.5

E. 17

Let a, b, and c be three distinct one-digit numbers. What is the maximum value of the sum of the roots of the equation (x-a)(x-b)+(x-b)(x-c)=0 ?

**Answer Choices**

A. 15

B. 15.5

C. 16

D. 16.5

E. 17