If the average (arithmetic mean) of a and b is 110, and the average of b and c is 160, what is the value of a − c?	Choose the correct choice from the following:
A) − 220 B) − 100 C) 100 D) 135 E) it can not be determined from the information given

Rationale: "( a + b ) / 2 = 110 = = = > a + b = 220 ( b + c ) / 2 = 160 = = = > b + c = 320 ( a + b ) - ( b + c ) = 220 - 320 = = = > a + b - b - c = - 100 = = = > a - c = - 100 answer : b"
Answer: B