Phototropic curvature is the result of uneven distribution of:

Options

(a) gibberellin
(b) Phytochrome
(c) cytokinins
(d) auxin

Correct Answer:

auxin

Explanation:

Phototrophic curvature is the result of uneven distribution of auxin. The experiments conducted by Charles Darwin concluded that the tip of coleoptile of canary grass contain auxin that causes the bending of the entire coleoptile towards the light source.