In a clinical trial, 12,00012,000 adults ages 5050 and above were randomly assigned to two groups. Group A received a new cholesterol-lowering drug, while Group B received a placebo. Participants were followed for 88 years to track the incidence of stroke. How does randomization address the influence of uncontrolled explanatory variables in this experiment?

It ensures both groups have similar distributions of all explanatory variables, known and unknown.

It guarantees that only the treatment affects the outcome.

It eliminates the need for a placebo group.

It allows researchers to ignore all confounding variables.

In a clinical trial, 12,00012,000 adults ages 5050 and above we...

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