Select the most appropriate meaning of the given idiom.

A change of heart

A change in one's opinion

The most appropriate meaning of the idiom "a change of heart" is a change in one's opinion.

The idiom is thought to have originated in the 16th century, and is thought to be based on the idea that the heart is the seat of emotion and thought. When someone has a change of heart, it means that they have changed their mind about something.

The idiom is now used more generally to describe any situation where someone changes their opinion or decision.

The other options are not as appropriate meanings for the idiom "a change of heart":

• To have a heart transplant: This is not the meaning of the idiom. A heart transplant is a medical procedure, not a change in opinion.
• To fail to fulfil a promise: This is not the meaning of the idiom. Failing to fulfil a promise is not the same as changing one's opinion.
• To have a second opinion: This is not the meaning of the idiom. Having a second opinion is about getting more information, not changing one's opinion.