Select the most appropriate idiom that can substitute the underlined segment in the given sentence.
I don't know which career he will choose. He delays making strong decisions.

The correct answer is sits on the fence.

Explanation:
The phrase "delays making strong decisions" refers to hesitating to choose between options or taking a side. The idiom "sits on the fence" precisely means to remain neutral or delay making a decision when faced with a choice.

Meanings of all options:
• sits on the fence: To delay making a decision, avoid taking a side, or remain undecided.
• is as clean as a whistle: Completely clean, clear, or free of guilt/wrongdoing.
• turns a blind eye: To deliberately ignore something bad or illegal.
• spills the beans: To reveal confidential information or a secret.

Therefore, the idiom "sits on the fence" is the most appropriate substitute for the underlined segment.