A) hypertonic, turgor pressure
B) hypotonic, turgor pressure
C) isotonic, a contractile vacuole
D) hypertonic, a contractile vacuole
E) hypotonic, a contractile vacuole
The correct answer is E. water enters protozoans by osmosis when they are in a hypotonic environment (the usual case for them) and the contractile vacuole eliminates excess water.
