Select the most appropriate option that can substitute the underlined segment in the given sentence. If there is no need to substitute it, select 'No substitution'.
This case is serious. You need to look into this matter; otherwise, the situation will get out of control soon.
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. No substitution.
"Look into" in the sentence means to investigate or examine a matter closely to understand it better or to find a solution.
It fits well in the context without needing any substitution.