The bathroom window in Parth's house has frosted glass

Why

Parth is correct that you can't see clearly through frosted glass — that part of his observation is true. But opaque doesn't mean blurry; it means no light gets through at all, like a wooden door or a brick wall. Ask a different question: in the daytime, with the door shut and the bulb off, is the bathroom dark? It isn't — daylight comes in through that window. So light IS passing through the glass; it just gets scattered on the way, which is why shapes look blurred. That in-between behaviour has its own name: translucent, like butter paper or a thin plastic bucket. Test: shine a torch at the frosted glass from one side and look from the other, then do the same with a wooden plank — the glass glows, the plank stays dark. Mitali is right: frosted glass is translucent, because it lets light through even though you can't see clearly through it.