The correct answer is B. According to the American Cancer Society, tobacco poses the greatest risk for developing cancers. It was estimated that there is a 22% deaths per year due to cancer caused by tobacco use. During 2004, about 1.6 million deaths were recorded due to cancer.
No the answer is not A because all your mucus builds up in your respiratory system not respiratory secretion. <span />
B.
Explanation: common sense
Answer:
1. Drugs during pregnancy
2. smoking to second smoke while pregnant
3.High caffeine consumption during pregnancy
4. Bipolar disorder
5. schizophrenia.
Alcohol use during pregnancy 6