The author developed the idea that experts are not sure why sitting for so long can hurt you this way:
B. The author states the central idea in a heading and then in the section provides details about multiple possible causes.
The author developed the central idea when he started off with the heading and first sentence. He highlighted the fact that scientists are not too sure about why sitting for too long can cause early death.
Many studies conducted by scientists were cited and all of these point to the possibility of cardiovascular attacks due to prolonged sitting.
They all recommended walking every half an hour as that could help them boycott the risks. In the conclusion, the main idea was strengthened.
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