Multiple choice biology the world of microbes protista protozoa five kingdoms of living organisms The main function of the contractile vacuole is Synthesis of carbohydrate Eliminating excess water To be a photoreceptor to detect light Resistance for survival during winter and times of drought Reveal answer Fill a bubble to check yourself B Correct answer Explanation The contractile vacuole is a structure found in many marine organisms. It functions as an organelle to eliminate the excess water which may have stored in the cell because of osmotic conditions.so, the correct option is 'eliminating excess water'