Let’s break this down.
The sentence says:
“…cleaving of the subcontinent into two mutually antagonistic parts…”
“Mutually antagonistic” means the two parts are opposed or hostile to each other.
Impartial → neutral, not taking sides → opposite of antagonistic.
Argumentative → more about tendency to argue, not strong enough for nations/groups in conflict.
Separated → describes the state of division, not the relationship.
Hostile → actively opposed, unfriendly, fits “antagonistic” closely.
Correct answer: D. Hostile