B is the only one that seems to make sense (though Mao was last year and I don't quite remember). A is wrong because the quote doesn't refer to actual schools. C and D aren't right because there's no way to infer those things from the quote.
The correct answer is - B. It called upon all intellectuals to voice their opinions about the workings of the Chinese Communist Party.
This move from Mao Zedong was very surprising and unexpected since his party has been responsible for shutting down the free speech in the country, and people that had tried to express their own opinion which if it was not the same as the one of the communist party ended up in jail or ''missing''. Now this move can be seen from two perspectives, from one side Mao Zedong tried to gain on popularity with it, and from the other side, lots of the intellectuals were actually people close to the communist party so their opinion was by far the most dominant.
As the Civil War began, President Lincoln accepted the belief that. individual states should settle the question of slavery. it was time to end slavery throughout the United States. the Union could be preserved as a mix of free and slave states.
Natural monopolies are allowed when a single company can supply a product or service at a lower cost than any potential competitor, and at a volume that can service an entire market.