To what extent have Aldous Huxley's Brave New World and George Orwell's 1984 explored the notion of challenging the status quo and questioning...

The idea that we should question and challenge political authority and the status quo is central to both 1984 and Brave New World. The novels envision different types of dystopia, but in each, loss of the power to think, challenge authority or make one's own decisions dehumanizes the population.

In 1984, the dystopia is one in which people live under the heel of a repressive state regime. Here, they live physically miserable lives with poor food, broken elevators, endless shortages of basic goods, continuous warfare and constant surveillance. Any shred of individualism or thinking for oneself is potentially a thought crime. The language is in the process of being dumbed down and reduced to the fewest number of words and concepts so that people won't have any apparatus for developing independent thought. 

In Brave New World, the population lives amid material plenty and without war. Rather than being openly miserable, people are conditioned from earliest youth to be happy with their lot. Yet they also are conditioned never to think for themselves, to live superficially and to avoid entering into deep relationship with another human being. They live in a banal world without real poetry, art, religion or grandeur. The goal is the absence of suffering, but this leads to a loss of humanity and autonomy similar to the loss people experience in 1984. In both cultures, people have been robbed of the ability to develop as individuals or to question their fate.

Brave New World was written before 1984. When 1984 appeared, Huxley wrote Orwell a letter. In it, Huxley naturally defended his own version of dystopia as more likely, writing

Within the next generation I believe that the world's rulers will discover that infant conditioning and narco-hypnosis are more efficient, as instruments of government, than clubs and prisons, and that the lust for power can be just as completely satisfied by suggesting people into loving their servitude as by flogging and kicking them into obedience. In other words, I feel that the nightmare of Nineteen Eighty-Four is destined to modulate into the nightmare of a world having more resemblance to that which I imagined in Brave New World.

The letter is relevant because it shows Huxley's awareness that both novels centrally concern governments robbing people of their individualism by forcing them, one way or another, to become obedient instruments of the state.