In the final match, our school team defeated the visiting one by 4 _____ 3.
The appropriate word for the completing the given sentence is “against”.
What is a sentence?
The sentence can be defined as a group of words that are arranged properly to convey a meaning.
For the given sentence, the correct word that make the sentence grammatically correct is against. The revised sentence will be “In the final match, our school team defeated the visiting one by 4 against 3.
Therefore the correct option is A.