In accordance with the decision of the High Court of Australia in David Securities Pty Ltd v Commonwealth Bank of Australia (1972)175 CLR 353, a mistake of law in a contract concerns:

a.

as the parties understood it to be at the date of the contract

b.

as the parties understood it to be at the date of initial negotiation prior to the date of contract

c.

as the parties understood it to be at any time regardless of entering the contract

d.

none of the above.