Select the most appropriate meaning of the given idiom.

A fire in someone’s belly

one who is energetic and enthusiastic about something

The most appropriate meaning of the idiom "a fire in someone's belly" is one who is energetic and enthusiastic about something.

The other options are incorrect.

• "One who is rich and powerful and exploits the poor" is not the same as a fire in someone's belly. This idiom refers to someone who is passionate about something, while the phrase "rich and powerful and exploits the poor" refers to someone who is greedy and selfish.
• "One who comes from a middle class background" is not the same as a fire in someone's belly. This idiom does not refer to someone's social class, while the phrase "comes from a middle class background" refers to someone's upbringing.
• "One who continues to work without wanting a reward" is not the same as a fire in someone's belly. This idiom refers to someone who is hardworking and dedicated, while the phrase "continues to work without wanting a reward" refers to someone who is selfless and unselfish.

The idiom "a fire in someone's belly" comes from the idea of a fire being a source of energy and heat. In the same way, someone who has a fire in their belly is someone who is full of energy and enthusiasm. They are passionate about something and are determined to succeed. For example, you might say that a young entrepreneur has a fire in their belly if they are very excited about their new business venture.