Fill in the blanks with the most appropriate option:-

Smoking is injurious to health. So, you must ___________ the habit.

give up

The most appropriate option to fill in the blanks is give up.

The sentence "Smoking is injurious to health. So, you must give up the habit." means that you must stop smoking, or discontinue the habit of smoking. This is because smoking is harmful to your health and can lead to serious health problems, such as lung cancer, heart disease, and stroke.

The other options are not appropriate because they do not convey the same meaning.

• Give away means to give something to someone else. This does not make sense in the context of the sentence, as you are not giving the habit of smoking to someone else.
• Give in means to surrender or give way to someone or something. This does not make sense in the context of the sentence, as you are not surrendering to the habit of smoking.
• Give out means to distribute something to a group of people. This does not make sense in the context of the sentence, as you are not distributing the habit of smoking to a group of people.