Trees，some of the tallest in the world，towered above Hannah Griffiths and her colleagues each morning as they walked deep into the rainforest in the Maliau Basin in Borneo，where they had set up a set of experiments to look at the ecological effects of small creatures：termites （白蟻）.
   Termites get a bum rap.They make headlines for chewing up billions of dollars of property each year in the US.And they are responsible for something like two percent of global carbon emissions，simply as a result of their huge populations and preference for chewing through carbon-rich materials.A whole industry is aiming at killing them.
   But they play a key role in many natural ecosystems.Scientists have known for years that in tropical （熱帶的） forests，termites chew up fallen leaves and dead wood，keeping the fallen material under control and letting nutrients from the dead material back into the system to be used by other plants，insects，and animals.But they didn't know exactly how important the insects were in keeping the forest healthy and functional，so they removed termites from a particular spot in the forest and saw how it responded.
   As luck would have it，Hannah Griffiths and her colleagues started their experiment when the forest was hit by an extreme drought.During the non-drought years，they saw there wasn't much difference between the normal plots and the ones where they'd removed the termites.But during the drought，the effects were marked.What they found was unexpected：in the termite-rich areas，the soil stayed slightly wet，more tree seedlings sprouted（抽芽），and the system was full of activity despite the long，hard dry spell.
   For Griffiths，it was only because they happened to study the drought that they could pick out the real importance of termites to the system，she points out."And that rings alarm bells in my head，" she says，"because it makes me think，well，what else don't we know？If we start damaging biological communities，we don't know what that will do."

（1）Which of the following best explains "a bum rap" underlined in Paragraph 2？

A

A

A．Unfair blame.
B．Wide popularity.
C．Public attention.
D．Special preference.
（2）What have scientists learned about termites？

B

B

A．They do serious harm to tropical rainforests.
B．They contribute a lot to the ecosystem they live in.
C．They act as food for other plants，insects and animals.
D．They speed up the loss of nutrition in the rainforest.
（3）What can we infer from the finding of Griffiths' experiment？

A

A

A．Termites help rainforests survive climate change.
B．Termites prefer drought years to non-drought ones.
C．Termites benefit more from the forest during the drought.
D．Termites enjoy eating tree seedlings during the drought.
（4）What does Griffiths tell us in the last paragraph？

C

C

A．Termites are now in danger of extinction.
B．Termites damage biological communities.
C．We should think twice before damaging a species.
D．We should study the drought to improve the system.