Question 90

Providing an overview of the causes of CF and how it is carried

The passage offers a comprehensive explanation of cystic fibrosis, detailing both its causes and the hereditary nature of the disease. It outlines how the defective gene leads to the symptoms associated with CF and explains the genetic inheritance pattern.

A) Describing the causes of cystic fibrosis

While the passage does mention the causes of cystic fibrosis, this choice is too narrow as it overlooks the discussion of how the disease is inherited. It does not fully encapsulate the dual focus on both causes and genetic transmission that the passage presents.

B) Explaining how cystic fibrosis is passed down through families

This option focuses solely on the inheritance aspect of cystic fibrosis. Although the passage addresses this topic, it also provides significant information about the causes of the disease, making this choice incomplete as it does not reflect the overall purpose of the passage.

C) Providing an overview of the causes of CF and how it is carried

This option accurately describes the passage's intent, which is to provide a broad overview that includes both the causes of cystic fibrosis and the details regarding its hereditary nature. It encapsulates the dual focus of the text effectively.

D) Reviewing why some Americans have CF, but others do not

This choice is too specific and does not encompass the general information provided about cystic fibrosis. The passage does mention who carries the CF gene, but it is not centered around why some individuals have the disease while others do not, thus making this option less relevant.

Conclusion

The correct answer, option C, is the most comprehensive as it captures both the causative factors of cystic fibrosis and the genetic inheritance patterns discussed in the passage. Other options either focus too narrowly on one aspect of the disease or fail to address the full scope of information provided, reinforcing why C is the definitive choice.