You Are Watching a Paramecium in Fresh Water and See

Multiple Choice

You are watching a Paramecium in fresh water and see a rounded structure within it enlarge and then suddenly contract as water is expelled.You have just witnessed the

A) food vacuole releasing excess water acquired through eating.
B) oral groove expelling water as food is ingested.
C) result of ciliary action involved in locomotion.
D) contractile vacuole keeping the organism's cytoplasm hypertonic to the environment.
E) expulsion of waste produced during digestion.