The tone of this passage is ______.A．criticalB．factualC．humorousD．romantic

The last paragraph of the passage shows the tone of the author is______.A．unconcernedB．ang

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

The central idea of this passage is that______.A．manners change with the passage of timeB．

The main idea of this passage is to explain______

The main purpose of this passage is to__________.

The main idea of this passage is to explain______