The main idea of this passage is ______.A．what the future of health care is likeB．how onli

The main idea of this passage is ______.

A．what the future of health care is like

B．how online doctors operate on patients

C．first-aid kit found wider uses

D．bandwidth is the limiting factor for transmitting images

请帮忙给出正确答案和分析，谢谢！