B-Cell Development Has One Checkpoint to Determine If V-DJ Rearrangement

B-cell development has one checkpoint to determine if V-DJ rearrangement has produced a successful V_H-DJ_H combination that does not recognize self.If no successful combination is produced, then the B cell will undergo apoptosis.At what point of B-cell development does this checkpoint occur?

A) Pre-pro-B cell
B) Early pro-B cell
C) Late pro-B cell
D) Late pre-B cell
E) Immature B cell