Answer: D. positive phototropism
Step-by-step explanation:
Tropism is a response shown by the plant towards an external stimulus like gravity, light, touch and water. The phototropism can be define as a response shown by the plant towards the sunlight. The positive phototropism can be shown when a plant part bends towards the incident beam of sunlight. This is typically shown by aerial parts like stems and leaves. The negative phototropism is shown by the roots which grow underground they do not require sunlight.
According to the given situation, the plant is showing the response towards the sunlight stimuli by bending therefore, it is an example of positive phototropism.