The answer here is actually quite obvious, considering the poor spelling and all.
The answer would be D; You are happier if you gave up that annoying habit.
To make this sentence sound slightly better, lets change some things so you can see the difference.
> I would be happier if you gave up that annoying habit.
> They may be happier if you gave up that annoying habit of yours.
Just 2 different ways to see that sentence, but do they sound any better? Please let me know if I'm incorrect about this answer or confusing you.