A. Trees are very important to human beings.

B. Studying tree rings can tell us the history of weather and man.

C. Weather can change the history of man.

D. A tree grows best in a climate with plenty of sunlight and rainfall.

A. Men never wear jackets and ties at all.

B. Men’s fashion changed as rapidly as women’s.

C. Men’s clothing hasn’t changed so much for several years.

D. Great changes have taken place in men’s clothing recently.