A survey of 400 randomly selected teenagers found that 57% own a smartphone, with a margin of error of ±5 percentage points at 95% confidence. A researcher claims that a majority (more than 50%) of all teenagers own a smartphone. Which statement best evaluates this claim?
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A
The claim is supported because the entire confidence interval (52% to 62%) is above 50%.
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B
The claim is not supported because the margin of error is too large to draw conclusions.
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C
The claim is uncertain because 50% is within one margin of error of the sample proportion.
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D
The claim is supported because the sample proportion of 57% exceeds 50%.