Neglecting Gravity,doubling the Exhaust Velocity from a Single Stage Rocket

Multiple Choice

Neglecting gravity,doubling the exhaust velocity from a single stage rocket initially at rest changes the final velocity attainable by what factor? Assume all other variables,such as the mass of the rocket and the mass of the fuel,do not change.

A) The final velocity stays the same.
B) The final velocity doubles.
C) The final velocity increases by a factor of 0.693.
D) The final velocity increases by a factor of 0.310.