Option (1) is incorrect: For the application of res judicata, previous suit should be finally heard and decided by the court of competent jurisdiction.
Option (2) is correct: For the application of res judicata, previous suit should be heard and decided by the court.
Option (3) is incorrect: Parties in the previous suit and subsequent suit must be same for the application of res judicata.
Option (4) is incorrect: Subject matter of previous and the subsequent suit must be the same for the application of res judicata.