英検準１級長文問題

英検準１級の長文問題です。

  The Fragile Banana     

  The banana is one of the world's most popular kinds of fruit, with about 80 million tons grown worldwide annually. Such a common fruit, you might suppose, could never disappear from our lives. The truth is some experts are warning that unless we take immediate action, the very existence of bananas could be at risk. To understand why, it is necessary to think about the fruit not in terms of the number grown but in terms of its genetic makeup. The greater the genetic diversity of a species, the more likely it is that some of its members will be able to resist new diseases. Unfortunately, virtually every banana that we see on supermarket shelves belongs to the same variety – the Cavendish. According to some experts, this limited genetic base means that most of the world's banana crop could be destroyed by just one disease.

The fact that this is not merely a wild theory is demonstrated by the fate of the Cavendish's predecessor, the Gros Michel. The large and tasty Gros Michel was the banana that filled most people’s shopping bags until the 1950s. Then plantations worldwide were hit by a sudden outbreak of Panama disease. Growers spent millions of dollars moving their trees into new areas in an unsuccessful attempt to avoid the disease. In fact, the only thing they succeeded in doing was to destroy huge areas of wild rain forest. In the end, the Gros Michel had to be replaced by the Cavendish, which had turned out to be resistant to the disease.

   It is not only the commercial popularity of the Cavendish that is reducing the genetic variety of bananas. The United Nation’s Food and Agriculture Organization (FAO) points to deforestation in India as another major area of concern. India's forests contain many kinds of wild banana, making them one of the richest sources of genetic variety in the fruit. "The Indian subcontinent has made an enormous contribution to the global genetic base of bananas," says FAO Agricultural officer NeBambi Lutaladio. But if deforestation continues at the current rate, he warns, the loss of diversity will definitely make global crops harder to replace. One solution, according to Lutaladio, is to provide more support for smaller, localized growers, who produce varieties of banana that are not vulnerable to the same diseases as the Cavendish. Variety, it seems, is not only the spice of life, but essential to its very survival.

(35) Why are some experts increasingly concerned about the future of the banana?

  1 The companies that dominate the banana trade tend to put profit before conservation.

  2 A new disease has just appeared that threatens banana crops around the world.

  3 The large-scale production of bananas is causing severe damage to the environment.

  4 Almost all bananas produced commercially today have the same genetic makeup.

(36) Why did the Cavendish variety of banana eventually replace the Gros Michel?

  1 The Cavendish banana was easier to grow and did less damage to the environment.

  2 The rain forests where the Gros Michel was produced suffered widespread damage.

  3 Companies found it too expensive to develop new plantations for the fast-growing Gros Michel.

  4 Growers found that the Cavendish was not affected by Panama disease.

(37) According to the FAO, what is one factor threatening the survival of the banana?

  1 The rising number of local markets in India selling wild bananas.

  2 The destruction of many varieties of wild banana in India.

  3 The difficulty in meeting the growing global demand for bananas.

  4 The loss of commercial banana plantations due to Panama disease.