Which Process Underlies the Thigmotropic Behavior of a Green Bean

Multiple Choice

Which process underlies the thigmotropic behavior of a green bean tendril?

A) rotation of the tendril in response to photoperiod
B) rotation of the tendril in response to a biological clock
C) extra proliferation of cells on the shaded side of the tendril
D) slower growth on the side where an object is touching the tendril