【2015·陕西】C
The production of coffee beans is a huge, profitable business, but, unfortunately, full-sun production is taking over the industry and bringing about a lot of damage. The change in how coffee is grown from shade-grown production to full-sun production endangers the very existence of, certain animals and birds, and even disturbs the world’s ecological balance.
On a local level, the damage of the forest required by full-sun fields affects the area’s birds and animals. The shade of the forest trees provides a home for birds and other special(物种) that depend on the trees’ flowers and fruits. Full-sun coffee growers destroy this forest home. As a result, many special are quickly dying out.
On a more global level, the destruction of the rainforest for full-sun coffee fields also threatens(威胁)human life. Medical research often makes use of the forests' plant and animal life, and the destruction of such species could prevent researchers from finding cures for certain diseases. In addition, new coffee-growing techniques are poisoning the water locally, and eventually the world's groundwater.
Both locally and globally, the continued spread of full-sun coffee plantations (种植园)could mean the destruction of the rainforest ecology. The loss of shade trees is already causing a slight change in the world's climate, and studies show that loss of oxygen-giving trees also leads to air pollution and global warming. Moreover, the new growing techniques are contributing to acidic(酸性的) soil conditions.
It is obvious that the way much coffee is grown affects many aspects many aspects of life, from the local environment to the global ecology. But consumers do have a choice. They can purchase shade-grown coffee whenever possible, although at a higher cost. The future health of the planet and mankind is surely worth more than an inexpensive cup of coffee.
What can we learn about full-sun coffee production from Paragraph 4?

A．It limits the spread of new growing techniques.

B．It leads to air pollution and global warming.

C．It slows down the loss of shade trees.

D．It improves local soil conditions.

The purpose of the text is to .

A．entertain

B．advertise

C．instruct

D．persuade

Where does this text probably come from ?

A．An agricultural magazine.

B．A medical journal.

C．An engineering textbook.

D．A tourist guide.

Which of the following shows the structure of the whole text?