In Which of the Following Situations Are the Parties to an Agreement

In which of the following situations are the parties to an agreement that is expressed to be 'subject to legal advice' able to change their minds about the agreement prior to the legal advice?

A) The parties intend the agreement to be legally enforceable immediately and simply propose to have the agreement restated more formally.
B) The parties intend the agreement to be legally enforceable immediately but they also intend to make another agreement that will eventually be substituted for the first agreement.
C) The parties do not intend the agreement to be legally enforceable until the legal advice is received.
D) The parties intend the agreement to be legally enforceable immediately but they also intend to terminate the agreement if recommended by the legal advice.