Select the most appropriate meaning of the given idiom.

Hard nut to crack

a difficult person or problem

The most appropriate meaning of the idiom "hard nut to crack" is a difficult person or problem.

The other options are incorrect.

• "Someone who solves puzzles easily" is not the same as a hard nut to crack. A hard nut to crack is someone who is difficult to understand or deal with, while someone who solves puzzles easily is someone who is good at figuring things out.
• "Someone who needs guidance" is not the same as a hard nut to crack. Someone who needs guidance is someone who is not sure what to do, while a hard nut to crack is someone who is difficult to understand or deal with.
• "A person who likes to joke around" is not the same as a hard nut to crack. Someone who likes to joke around is someone who is playful and lighthearted, while a hard nut to crack is someone who is difficult to understand or deal with.

The idiom "hard nut to crack" comes from the idea of trying to crack a nut with your teeth. This is a difficult task, and it requires a lot of force and determination. In the same way, someone who is a hard nut to crack is someone who is difficult to understand or deal with, and it takes a lot of effort to get through to them. For example, you might say that a difficult customer is a hard nut to crack.