A fraudulently informs B that A's property is free from encumbrance. B thereupon buys the property . The property is subject to a mortgage. In this case –
1
B may avoid the contract
2
B may either avoid the contract or may insist on it’s being carried out and the mortgage-debt redeemed.
3
B may continue with the contract with A.
4
The contract is void and hence unenforceable.