Vinblastine interferes with tubulin function, thus disrupting the migration, phagocytosis, degranulation, and cytoskeleton of neutrophils

This question is testing your knowledge on microtubule inhibitors (all are M-phase specific).

Specifically, this question is asking you about Vinblastine. One important adverse effect to know about vinblastine (blasts the marrow): myelosuppression. Therefore, you would see a significant decrease in the numbers of neutrophils.