A Series Circuit Consists of a 100 V DC Power

Multiple Choice

A series circuit consists of a 100 V DC power source,a 100 Ω resistor,and a variable resistor of resistance R,which varies from 0 to 100 Ω.The current in the circuit is

A) directly proportional to R.
B) inversely proportional to R.
C) directly proportional to (100 Ω + R) .
D) inversely proportional to (100 Ω + R) .
E) neither directly nor inversely proportional to R or to (100 Ω + R) .