A recent study found that people who drink coffee daily have a lower

Question

A recent study found that people who drink coffee daily have a lower risk of developing Alzheimer's disease. The study surveyed 1000 people over the age of 60, of whom 500 drank coffee daily and 500 did not. Of the 500 coffee drinkers, only 50 developed Alzheimer's disease, while 100 out of the 500 non-coffee drinkers developed the disease. Therefore, drinking coffee daily reduces the risk of Alzheimer's disease.    1 
 Which of the following statements, if true, would weaken the argument above? 
 
A) The study did not take into account the participants' family history of Alzheimer's disease.
B) The study did not take into account other lifestyle factors that may affect the development of Alzheimer's disease.
C) There is evidence that coffee can increase blood pressure in some people.
D) The participants in the study who drank coffee daily also tended to exercise more and eat a healthier diet.
E) The study only surveyed participants in one geographical region and may not be representative of the wider population.

Sajjad1994 · Answer

OE

Step 1: Understand the Argument

Premise:    A study of 1,000 people over 60 found that:

- 50 out of 500 coffee drinkers developed Alzheimer’s. 
 - 100 out of 500 non-coffee drinkers developed Alzheimer’s.

Conclusion:   Drinking coffee daily reduces the risk of Alzheimer’s disease.

Step 2: Identify the Question Type

This is a  "Weaken the Argument"  question. We need to find a statement that undermines the causal claim that coffee reduces Alzheimer’s risk.

Step 3: Look for Potential Weaknesses in the Argument

The argument assumes that coffee is the  only  factor affecting Alzheimer’s risk. However, other variables (e.g., genetics, diet, exercise) could explain the difference. A good weakener will introduce an  alternative explanation  or  confounding factor .

Step 4: Evaluate the Answer Choices

A)    This suggests genetics could be a confounding factor. However, it doesn’t directly explain why coffee drinkers had lower rates. Weak weakener.

B)    This is broad and hints at confounding variables, but it doesn’t specify which factors.

C)    Irrelevant. The argument is about Alzheimer’s, not blood pressure.

D)   Strong weakener!    This provides an alternative explanation: healthier habits (not coffee) may have caused the lower Alzheimer’s risk.

E)    This critiques generalizability, but it doesn’t directly challenge the causal link.

Answer: D

A recent study found that people who drink coffee daily have a lower

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