Before choosing an option, it helps to fix the meaning of each term used in law, since the four options are all real legal expressions but none of the wrong three actually means a one-sided agreement.
Since three of the four terms describe something other than the fairness of a contract's terms, and only the fourth term is defined by that unfairness, unconscionable contracts is the only label that logically matches one-sided agreements.
The correct answer is unconscionable contracts.
The most likely source of confusion in this question is between unfair trade practice and unconscionable contract, since both use the word unfair. Separating these two, and then quickly disposing of the remaining two options, gives the answer.
By first separating the two unfair-sounding options on the basis of conduct versus terms, and then ruling out the two options that do not even involve a real, existing agreement or that address only how acceptance occurs, the field narrows to a single option.
So the correct answer is unconscionable contracts.