Final answer:
A repeating decimal is a decimal number that has a pattern that repeats infinitely. Option C, 6.787878, is an example of a repeating decimal.
Step-by-step explanation:
A repeating decimal is a decimal number that has a pattern that repeats infinitely. In this case, the best example of a repeating decimal is option C, 6.787878. The digits 78 repeat in a pattern.
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