Which type of contracts are characterized by terms that have not been fully executed?

The correct answer is executory contracts, as they are defined by the fact that some of the terms remain to be fulfilled or executed. In an executory contract, one or both parties have obligations that have yet to be performed. This could mean that a payment has not yet been made, goods have not yet been delivered, or services are still to be rendered, indicating that the contract is not yet complete.

In contrast, fiduciary contracts involve a relationship of trust and confidence, mainly focusing on the responsibilities of one party towards another. Implied contracts are derived from the actions or conduct of the parties rather than specific verbal or written agreements, which does not directly address the execution status of terms. Completed contracts, by definition, are those in which all terms have been fulfilled, making them the opposite of the question's focus on non-fully executed terms. Thus, executory contracts stand out as the appropriate choice in this context.