On dissolution of a partnership firm, if a partner undertakes the responsibility to make payment of a liability of the firm, then, the account to be debited is:

Realisation Account

The correct answer is option 1- Realisation Account.

On dissolution of a partnership firm, if a partner undertakes the responsibility to make payment of a liability of the firm, then, the account to be debited to Realisation Account.

For a liability which a partner takes responsibility to discharge, the journal entry will be: 
Realisation A/c Dr.
    To Partner’s Capital A/c