Answer:
The opponents sat opposite to each other.
In this sentence, the preposition "opposite" is the most appropriate choice to indicate the positioning of the opponents. When we say that two people are sitting opposite to each other, it means they are facing each other. This preposition implies a direct, face-to-face arrangement.
For example, imagine two people sitting across from each other at a table. They are sitting opposite to each other, with their positions mirroring each other.
Therefore, the correct preposition to fill in the blank is "opposite."
Step-by-step explanation:
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