Multiple choice

Phototrophic movements of roots and stems are due to

  1. action of gravity

  2. effect of light

  3. differential hormonal effect

  4. epinasty and hyponasty

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

 This option is correct because phototropism is directional growth in which the direction of growth is determined by the direction of the light source. In other words, it is the growth which response to a light stimulus.