Select the most appropriate meaning of the given idiom.
an open book
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. a person or thing that is easy to learn about and understand.
Idiom:
An open book
Meaning:
A person or thing whose thoughts, feelings, or intentions are easily known or understood
Example:
He is an open book; you can always tell what he is thinking.
Hence, the chosen option will be correct.