Which of the Following Statements Best Describes the Movement of IAA

Which of the following statements best describes the movement of IAA in a shoot tip?

A) IAA initially moves laterally from the shoot tip via polar transport.
B) IAA initially moves laterally from the shaded to illuminated side of the shoot tip.
C) IAA initially moves laterally from the illuminated to shaded side of the shoot tip.
D) IAA initially moves laterally from the shoot tip via nonpolar transport.