(C) Only I, III and IV are correct.
Statement II is incorrect because power sharing does not barricade (delay/block) decision-making as an argument in favour of it — that is an argument against it.
The question tests knowledge of arguments in favour of power sharing. Statement II ("Barricades the decision-making process") is actually a criticism/argument against power sharing (opponents argue it slows decisions). Statements I, III, and IV — reducing bias, accommodating diversities, and increasing people's participation — are all standard prudential/moral reasons given in favour of power sharing, as discussed in Chapter 1.