115.
The answer is: C
Explanation
The correct option is C: both (a) and (b).
Set-off can be either legal or equitable, depending on the nature and circumstances of the claims involved.
Legal set-off is a statutory right that allows a debtor to reduce or discharge a debt by setting against it a distinct claim in favor of the debtor against the creditor. Legal set-off can only be applied when both claims are liquidated (i.e., fixed and certain in amount) and due and payable.
Equitable set-off is a common law remedy that allows a debtor to withhold or reduce payment of a debt by setting against it a cross-claim that is connected with the debt. Equitable set-off can be applied when the cross-claim is unliquidated (i.e., not fixed and certain in amount) or not due and payable, as long as there is a close relationship between the two claims.