Which of the following statements is true? a. teens who smoke suffer from shortness of breath almost 3 times as often as teens who do not smoke b. a smoker's heartbeat is 3 times faster than a non-smoker's c. three out of four young people who smoke say then keep smoking because it is really hard to quit d. all of the above

exposure to hazardous carcinogens and toxic substances can cause breathing problems, such as copd and various types of cancer. it also increases the risk of heart attacks and strokes and has serious (but no less unattractive) side effects, such as aging, yellow teeth, a terrible smell and damage to the vocal cords.

frequency is the answer

i think your answer is a. coordination