The activity of a kinase called Src is regulated by phosphorylation. 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). Full activation of Src requires removal of the inhibitory phosphate group and binding to an activated RTK.

Based on this information, which statement about the activity of Src kinase is correct? Choose one:

a. The kinase is active only when Tyr527 is dephosphorylated and Tyr416 is phosphorylated.

b. The kinase is active only when Tyr416 is phosphorylated.

c. The kinase is active only when Tyr416 is dephosphorylated.

d. The kinase is active only when Tyr527 is phosphorylated and Tyr416 is dephosphorylated.

e. The kinase is active only when Tyr527 is dephosphorylated.

f. The kinase is active only when Tyr527 is phosphorylated.