To What Does the 9 + 2 Arrangement of Microtubules,typical

Multiple Choice

To what does the 9 + 2 arrangement of microtubules,typical of cilia and eukaryotic flagella,refer?

A) the arrangement of dynein arms with respect to each microtubule
B) the arrangement of microtubules within the axoneme
C) the spoke-like arrangement of the cross sections of cilia or flagella
D) the relationship between the basal body and the axoneme