Answer:
The answer is letter B.
Step-by-step explanation:
The kinase is inactivated by phosphorylation at a C-terminal tyrosine residue (Tyr527) and is activated by interaction with an activated RTK, which stimulates Src to autophosphorylate a different tyrosine residue (Tyr416).
Because the kinase is exclusively active when Tyr527 is dephosphorylated and Tyr416 is phosphorylated.