That would be D.
Why?
Answer choice A is a rational number. Square root of a 100 is 10, which a rational number.
Answer choice B is a rational number. All fraction, is a rational number, regardless of any numbers.
Answer choice C is a rational number. It's a number that has a decimal points that stops. In other words, it doesn't have repeating decimal numbers, meaning that it is a rational number.
Answer choice D is irrational. The cube root of 16 has a number that has decimal numbers that have no pattern and continues to go on forever.
Hope this helps.
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