Read the following passage and mark A, B, C, or D to indicate the correct answer to each of the blanks.

More than two hundred years ago, the term “environmental pollution” was quite strange to people. They lived healthily, drank ___(1)___ water and breathed fresh air. In those days, industry was not well-developed. Nowadays, the situation is quite different. The world today is faced with many ___(2)___ threats. People all over the world are worried ___(3)___ things that are happening to the environment. Actually, it is man ___(4)___ is destroying the surroundings with many kinds of wastes from the devices that makes human live more comfortable and convenient. Everybody knows that motorbikes and cars emit dangerous gases that cause poisonous air and cancer, but no one wants to travel on foot or by bicycle. Manufactures know that wastes from factories make water and soil polluted, but they do not want to spend a lot of their money on ___(5)___ the wastes safely. Scattering rubbish is bad for our health, but no one wants to spend time burying it. Is it worth talking a lot about pollution?