3．Mountain regions are not just playgrounds for the richer citizens on the planet，however．The disappearing snows of Mount Kilimanjaro are a worrying sign that nowhere is safe from the adverse effects of human actions．The United Nations has identified three main areas that need to be addressed to ensure the future safety of the world's mountains．These are：the protection of mountain ecosystems，the encouragement of peace and stability in mountain regions，and assistance for mountain people to maintain their ways of life．
From the busy cities of India to the farmlands of California，more than half the world's population is dependent on mountains for their fresh water supply．Global warming，deforestation，mining and heavy farming seriously damage breakable mountain ecosystems and put vital fresh water sources at risk．
Mountain regions host a large proportion of the world's wars．From Afghanistan to the Balkans and the Andes to many parts of Africa，territorial（领土的） and drug related conflicts have damaging effects on the local environment and the lives of the local people．Fighting makes essential tasks such as farming impossible．Land mines make large areas of potential farming ground unusable．Also schools，roads，bridges and other important infrastructure（基础设施） are left in ruins．
Mountain people are among the poorest，least represented groups on the earth．They face many hardships and each day can be，"a test of survival"．Damage to mountain ecosystems worsens their situation and leaves them even more unprotected to disease and‘natural'disasters such as floods and landslides．It's been recommended that forest profit should be reinvested in mountain communities and the people living there should be given a stronger political voice．Their fate is in many ways directly connected with that of people living at sea level．
There is an old motto for visitors to the countryside which advises them to leave nothing but footprints．It is still as relevant today as it always was．Unfortunately，the size of our footprints seems to be getting larger．
68．What the writer discussed in the previous sections is most probably aboutD．
A．mountain ecosystems
B．mountain regions
C．mountain people
D．mountain sports
69．The word"adverse"（paragraph 1）is closest in meaning to"C"．
A．direct
B．positive
C．harmful
D．powerful
70．Wars have directly brought the following effects EXCEPTA．
A．inadequate supply of fresh water
B．impossible farming
C．mountain people's poor living condition
D．ruined infrastructure
71．Which of the following can be inferred from the passage？B
A．Mountain people have enough political voice to protect themselves．
B．Worsened ecosystems put mountain people's lives under threat
C．More money should be raised to establish mountain communities．
D．Visitors to mountains have left nothing but large footprints．
