A Couple Who Does Not Have Cystic Fibrosis but Are

question 12

Multiple Choice

A couple who does not have cystic fibrosis but are both heterozygous has already had three girls with cystic fibrosis, and are hoping to have a normal child for their fourth. What are the chances that the fourth child will be a normal male?

• A) 0
• B) 1/8
• C) 1/4
• D) 3/8
• E) 1/2

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Definitions:

Ecologic Study

A type of epidemiological study where the units of analysis are populations or groups of people rather than individuals.

Recall Bias

A systematic error caused by differences in the accuracy or completeness of the recollections retrieved by study participants about past events or experiences.

Case-control Study

A research design in which participants with a certain outcome or disease are compared to those without, to identify and evaluate risk factors or outcomes.

Cholera Infections

A highly contagious bacterial disease causing severe diarrhea and dehydration, usually spread through contaminated water.