What is meant by "regrettable reliance" in contract law?

Regrettable reliance refers to a situation where an individual has relied on a promise or assurance that turns out to be unenforceable, and this reliance has resulted in some form of detriment or harm. In contract law, this often arises in scenarios where one party takes action based on the belief that a valid contract or agreement exists, only to later discover that the agreement is not legally enforceable.

In the context of option B, the focus is on the consequences of relying on a promise that lacks legal enforceability. This reliance can lead to a party incurring costs, making investments, or changing their position based on the expectation that the promise would be honored. When the promise is ultimately unenforceable—perhaps due to a lack of formal requirements for a contract or other legal standards—this leads to regret regarding the reliance placed on that promise, hence the term "regrettable reliance."

In contrast, the other options do not encapsulate the concept accurately. Dependence on a valid agreement does not involve regret since that reliance is legitimate and enforceable. Reliance on verbal agreements that are enforceable would not fall under the category of regrettable reliance, as it suggests a sound basis for trust. Therefore, option B correctly captures the essence