When a Star Settles Down to a Stable Existence as a Main-Sequence

Multiple Choice

When a star settles down to a stable existence as a main-sequence star, what characteristics determines where on the main sequence in an H-R diagram the star will fall?

A) its mass
B) the fraction of its atmosphere that consists of hydrogen
C) whether it is located on the outer regions or the central regions of the molecular cloud that gave it birth
D) the speed and direction of its rotation
E) the size of the disk around it