What happens immediately after insulin binds to the α-subunit of the insulin receptor?

A) It activates the adjacent tyrosine kinase (β-subunit)
B) It increases glucose uptake by the cell
C) It stimulates glucagon secretion by the α cells
D) It stimulates the synthesis of GLUT-4 (glucose transporter-4)
E) It transports the GLUT-4 protein to the cell membrane