It can be concluded that ______.A．raising the world's temperature only a few degrees would

It can be concluded that ______.

A．raising the world's temperature only a few degrees would not do much harm to life on earth

B．lowering the world's temperature merely a few degrees would lead many major farming areas to disaster

C．almost no temperature variations have occurred over the past decade

D．the world's temperature will remain constant in the years to come