Which of These Statements Correctly Describes the Rotation of the Milky

Multiple Choice

Which of these statements correctly describes the rotation of the Milky Way Galaxy?

A) The disk rotates like a solid object (objects at all distances take the same time to complete an orbit) , and the globular clusters have random orbits with no net rotation of the halo about the center of the Galaxy.
B) Objects in the disk have random orbits with no net rotation of the disk about the center of the Galaxy, and the globular clusters rotate differentially (objects farther from the center take longer to complete an orbit than objects closer to the center) .
C) The disk rotates differentially (objects farther from the center take longer to complete an orbit than objects closer to the center) , and the globular clusters rotate differentially (objects farther from the center take longer to complete an orbit than objects closer to the center) .
D) The disk rotates differentially (objects farther from the center take longer to complete an orbit than do objects closer to the center) , and the globular clusters have random orbits with no net rotation of the halo about the center of the Galaxy.