It should not be controversial: it would only make the research less reliable since people would have their opinions about the topic that they would want to defend. It should also not be obscure: then it's hard to check.
The best answer is that it should be multifaceted: it should include a number of aspects, not just one, so that the test can check for those aspects, not just one.
Well it all depends on what you're writing about. When you write your rough draft think about the feeling it gives when reading it over. Then if it feels right, give it a go. This might not help much but think about how you feel while reading it.
I WOULD THINK THE CORRECT ANSWER WOULD BE B STEER AWAY BECAUSE IF YOU SPEED UP YOU WILL END UP HITTING WHATS IN FRONT OF YOU SOONER AND HARDER AND IT ALREADY STATES YOU DONT HAVE ENOUGH ROOM TO STOP SO BRAKING WOULDN'T HELP IM GUESSING
