The correct option is C Thigmotropism
Most vines and other climbing plants have tendrils that coil rapidly around supports. These grasping organs usually grow straight until they touch something; the contact stimulates a coiling response caused by differential growth of cells on opposite sides of the tendrils, the directional growth in response to touch is called thigmotropism, and it allows the vine to take advantage of whatever mechanical supports it comes across as it climbs upward toward a forest canopy.