A Refracting Telescope Has a Magnification M $M / 2$ B) $2 M$

Multiple Choice

A refracting telescope has a magnification M. If the focal length of the objective lens is doubled and the eyepiece focal length is halved, what is the new magnification?

A) $M / 2$
B) $2 M$
C) $M / 4$
D) $M$
E) $4 M$