Growing yam tendrils climb for support. This growth response is

A.

haptotropism

B.

geotropism

C.

phototropism

D.

hydrotropism

E.

chemotropism

Correct answer is A

-  Haptotropism / thigmotropism is the movement or change in orientation of a plant's growth as a reaction to touch. The orienting factor is generally a hard surface that can change the direction of the plant's growth or the growth of one of its organs.

- The movement of parts of a plant (especially tendrils) in response to a touch stimulus.