Healthy living habits do not include () A. A small amount of smoking and drinking B. Good sleep quality C. Moderate exercise D. Pay attention to the rules of three meals.

Healthy lifestyle includes: regular life, reasonable diet, rational drug use, sincere friendship between students of the opposite sex, active participation in recreational activities and sports, no smoking, no drinking, refusal to take drugs, etc.

A drinking and smoking are harmful to the respiratory system, nervous system and liver.

B, a regular life can form good habits, form a biological clock, improve the excitability of the nervous system, and improve the body's immune ability.

C, moderate exercise can enhance physical fitness, improve immunity, and is conducive to healthy growth.

D, reasonable diet, balanced nutrition, three meals a day on time, can not only meet the demand for nutrients, but also avoid obesity or malnutrition caused by excessive intake, which does not meet the question.

So choose: a