Select the most appropriate meaning of the given idiom.

A stumbling block

An obstacle to progress

The most appropriate meaning of the idiom "a stumbling block" is an obstacle to progress. It is used to describe something that makes it difficult or impossible to move forward. The idiom comes from the idea of a person stumbling over a block in their path, which would make them fall and slow them down.

The other options are not correct.

• Removing stones on the way: This is not the same as a stumbling block.
• Putting stones along the way: This can be part of creating a stumbling block, but it is not the whole meaning.
• Skipping over a hurdle: This is the opposite of a stumbling block.