Which of the following represents a lawful excuse for non-performance of a contract?

A lawful excuse for non-performance of a contract occurs when an unforeseen event or circumstance makes it impossible or impractical for a party to fulfill their contractual obligations. In this context, a force majeure event is a legal concept that refers to extraordinary events or circumstances beyond the control of the parties, such as natural disasters, wars, or other significant disruptions that prevent performance. When a force majeure event occurs, the affected party can often excuse themselves from fulfilling their contractual duties without facing legal consequences, as the event was beyond their control.

The other choices do not qualify as lawful excuses for non-performance. A personal disagreement between the parties simply reflects relational issues that do not invalidate the contract. A mutual mistake regarding contract terms can sometimes provide grounds to rescind the contract, but it doesn’t necessarily excuse non-performance in the sense typically recognized by law. Unfavorable market conditions may lead a party to feel unable to perform economically, but this does not constitute a legally acceptable reason for non-performance under most contracts.