델타스 NG 토플(Delta's Toefl Reading Sections)--Referents<2>
Some foods require very specific enzymes for digestion. Milk sugar, which is called lactose, needs an enzyme called lactase to convert it to glucose and galactose, carbohydrates needed by the body for energy. Some people do not produce lactase or have a deficient amount of the enzyme. Lactase deficiency may be inherited, and in infants it occurs in severe form, persisting throughout life. Some people develop the condition later in life, many when they are in their forties. People of Asian or African heritage develop the condition more frequently. Around 90 percent of the former and 75 percent of the latter have varying severity of lactase deficiency. People with the disorder, also called lactose intolerance, have difficulty digesting cow's milk. The condition is currently considered incurable; however, symptoms can be controlled and relieved with a diet free of milk and milk products.
The phrase the former in the passage refers to
O people in their forties
O people of Asian heritage
O people of African heritage
O people with the disorder
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What is the referent of the former? In all cases where two things are mentioned. the former refers to the first thing, and the latter refers to the second thing. In this passage, the former refers to people of Asian heritage because this phrase is mentioned first in the previous sentence. The latter refers to people of African heritage because this phrase is mentioned second.
The correct answer is people of Asian heritage. You can check this by reading the sentence with people of Asian heritage in place of the former and people of African heritage in place of the latter. The passage will read: People of Asian or African heritage develop the condition more frequently. Around 90 percent of people of Asian heritage and 75 percent of people of African heritage have varying severity of lactase deficiency.