1. Sponges have a water transport or canal system. 2. Water enters through minute pores (osculum) in the body wall into a central cavity, spongocoel, from where it goes out through the ostia. 3. This pathway of water transport is helpful in food gathering, respiratory exchange and removal of waste. Regarding 1,2 and 3:

Question

( a ) 3 is incorrect but 1 and 2 are correct
( b ) 1 is incorrect but 2 and 3 are correct
( c ) 2 is incorrect but 1 and 3 are correct
( d ) 1 is correct but 2 and 3 are incorrect