Two things happened today in Beijing . First off , incoming journalists were amazed to find China had successfully lifted the brown haze in city . Skies were crystal blue and the air felt noticeably lighter .
Why did the sky appear clearer ?
Pick the best answer from the following options:
- The citizens learned to ignore the gloomy skies .
 - The smog cleared after dangerous chemicals had been removed .
 - None of the above choices .
 - A large storm had recently passed .


The smog cleared after dangerous chemicals had been removed .