The correct option is D Illegal forest fires in Neil islands have spread poisonous gases across Viber island and many south-east Asian islands over the last few weeks, and have caused shut-down of certain normal activities in these islands.
Illegal forest fires in the area have spread across poisonous gases in other neighbouring regions, due to which few normal societal activities have shut down. We can also infer that this fire has spread across various other islands in that area. (IV) best captures the essence. (I) is narrow, it just talks about spreading of poisonous gases and not its consequence on human activities. (II) is narrow because it just talks about interrupted activities in Viber islands when the passage also mentions of other neighbouring islands. (III) is incorrect because it talks about interruption in all normal activities in the area whereas passage talks about only certain such activities, we cannot infer that all normal activities were interrupted.