I need help please.
The American Cancer Society has issued a timetable of the benefits that result when a person quits smoking. Within twenty minutes, heart rate and blood pressure drop closer to normal. Within twelve hours, the level of carbon monoxide in the blood returns to normal. Within two weeks to three months, blood circulation improves and lung functioning increases. Within one to nine months, there is a decrease in coughing and shortness of breath, and the cilia of the lungs regain their normal functioning. Within a year, the excess risk of coronary heart disease is half that of a smoker. After two to five years, the risk of a stroke is dramatically lower. Within five years, the risk of cancers of the mouth, throat, esophagus, and bladder drops by 50%, and the rate of cervical cancer is the same as that of a nonsmoker. Within ten years, the risk of dying from lung cancer is about half that of a smoker. Within fifteen years, the risk of coronary heart disease is no higher than a nonsmoker's.

The selection’s main pattern of organization is: (Click on the pattern of organization.)

a. definition and example.

b. comparison.

c. contrast.

d. cause and effect.

The text provided uses words like within and after. These words are common transition words used when explaining the effect and its cause. Example from the text: "Within twenty minutes, heart rate and blood pressure drop closer to normal." The sentence begins with the transition words within. The beginning of the whole text begins w/ stating the cause: "The American Cancer Society has issued a timetable of the benefits that result when a person quits smoking." After that sentence, they begin to list various effects that occur when a person quits smoking. Due to this information, one can conclude that the correct answer is d. cause and effect.