Answer:
Semipermeable
Explanation:
A semipermeable membrane is a polymeric and biological membrane present in the living organisms which allows the passage of uncharged and small solute, water and lipid-soluble molecules.
In the given question, the import and export of the material in response to the stimuli are performed through the semipermeable plasma membrane .The plasma membrane does not allow the passage of large molecules.
Thus, the semipermeable membrane is the correct answer.