Explain how an immune response starts after a macrophage attacks a pathogen

After the macrophage fails the Helper T Cell stimulates the B cells (create antibodies) if pathogen is extracellular and Cytotoxic T Cells (killer T cells, release perforin) if pathogen is intracellular. Once the pathogen is killed the B Cells create Memory B Cells and the Killer T Cells create memory T Cells. 

Hopefully I helped answer your question :)

Ithink the answer is d.