Question

which of the following observations is an example of a positive correlation? multiple choice - when members of a population consume fewer fruits and vegetables, their risk of high blood pressure increases. - when women gain less weight than average during pregnancy, the birthweights of their babies tend to be lower than average. - when a group of children increases their physical activity levels, the percentage of the children who contract cold infections decreases. - when a populations intake of green tea increases, the percentage of lung cancer cases in that population decreases.

Explanation:

A positive correlation means that as one variable increases, the other variable also increases (or as one decreases, the other decreases). Let's analyze each option:

• First option: Consuming fewer fruits/vegetables (decrease) leads to increased high blood pressure risk (increase) – this is a negative correlation (one decreases, the other increases).
• Second option: Women gaining less weight (decrease) during pregnancy leads to lower birth weights (decrease) of babies – as one decreases, the other decreases, which is a positive correlation.
• Third option: Increased physical activity (increase) leads to decreased cold infections (decrease) – negative correlation (one increases, the other decreases).
• Fourth option: Increased green tea intake (increase) leads to decreased lung cancer cases (decrease) – negative correlation (one increases, the other decreases).

Answer:

B. When women gain less weight than average during pregnancy, the birthweights of their babies tend to be lower than average.