Topic: Group verb,

Best Answer Explained in Below-:

The phrase "give up" is commonly used to indicate the act of quitting or abandoning a habit or practice. In the context of the question, "You should _____ your bad habit of smoking," the term "give up" directly implies that one should stop smoking, which is a detrimental habit linked to numerous health issues.

In contrast, the other options do not fit this context:

- **A) Give in:** This suggests surrendering to temptation or yielding to something, which does not convey the intention of quitting a bad habit.

- **C) Give away:** This means to distribute something to others, which does not apply to a personal habit like smoking. One cannot "give away" a habit.

- **D) Give out:** This generally refers to exhaustion or distributing items, neither of which accurately conveys the idea of stopping the act of smoking.

Thus, "give up" is the best choice, as it clearly communicates the idea of overcoming and moving away from a harmful behavior.