53.
The answer is: C
Explanation
The correct option is C: Both (a) & (b).
This is because the principle of res judicata can apply between co-defendants as well as between co-plaintiffs, subject to certain conditions. Res judicata means that a matter that has been finally decided by a competent court cannot be reopened or re-agitated in a subsequent suit. The doctrine is based on the maxims of nemo debet bis vexari pro una et eadem causa (no man shall be vexed twice for the same cause), interest reipublicae ut sit finis litium (it is in the interest of the state that there should be an end to litigation), and res judicata pro veritate accipitur (a judicial decision must be accepted as correct).
According to section 11 of the Code of Civil Procedure, 1908, res judicata applies when the matter has been directly or substantially in issue in a former suit between the same parties or between parties under whom they or any of them claim, litigating under the same title. The decree in the former suit would operate as res judicata between the plaintiff and the defendant or as between the co-plaintiffs or co-defendants. However, for res judicata to apply between co-defendants or co-plaintiffs, the following conditions must be satisfied:
- There must be a conflict of interest between co-defendants or co-plaintiffs;
- It must be necessary to decide the conflict in order to give relief to the plaintiff;
- The question between co-defendants or co-plaintiffs must have been finally decided; and
- The co-defendants or co-plaintiffs were necessary or proper parties in the former suit.
Therefore, option C is correct as it includes both (a) and (b), which are possible scenarios where res judicata can apply, provided that the above conditions are met. Option A is incorrect as it only includes one scenario. Option B is incorrect as it only includes one scenario. Option D is incorrect as it denies both scenarios.