You Have Discovered a Previously Unidentified Plant, and You Cultivate

Multiple Choice

You have discovered a previously unidentified plant, and you cultivate it in your lab. You notice that its flowers close when people are talking yet are open when the lab is relatively quiet. You suspect that this plant may have the ability to hear! Which of the following hypotheses is (are) the most reasonable to explain this phenomenon?
I. There is a cell-surface protein on the epidermal cells that becomes phosphorylated in response to vibration by sound waves.
II. There are tiny hairs on epidermal cells that bend in response to the vibration of sound waves, triggering an action potential in epidermal cells.
III. There is a cell-surface receptor on root cells that becomes phosphorylated when the soil vibrates in response to sound waves.

A) only I
B) only II
C) only III
D) only II and III
E) I, II, and III