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 its causes and the genetic factors influencing its inheritance. It outlines the role of the defective gene, the implications of mucus buildup, and the inheritance pattern of the disease.

A) Describing the causes of cystic fibrosis

This option is partially correct as it touches on the causes of cystic fibrosis, but it fails to encompass the broader context of the passage. The passage does not solely focus on the causes but also includes information about inheritance and the implications of the disease, making this option incomplete.

B) Explaining how cystic fibrosis is passed down through families

While this option addresses a key aspect of the passage, it is too narrow. The passage does provide details on how cystic fibrosis is inherited, but it also discusses the causes and effects of the disease, which are not covered by this option alone.

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

This option accurately captures the essence of the passage. It encompasses both the causes of cystic fibrosis and the hereditary nature of the disease, reflecting the comprehensive information presented in the extract.

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

This option is limited in scope as it focuses only on the prevalence of cystic fibrosis among certain groups. Although the passage mentions that millions of Americans carry the CF gene without symptoms, it does not specifically review the reasons for the variability in disease manifestation among Americans.

Conclusion

Option C is definitively the correct answer as it encapsulates the full range of information provided in the passage regarding both the causes of cystic fibrosis and the genetic inheritance involved. The other options, while addressing certain aspects of the content, fail to provide a complete overview as required by the question.