Which one of the following is an example of a repeating decimal? A) \( 0.666666 \overline{6} \) B) 0.123321 C) 1.234545 D) \( 6.7878 \overline{88} \)

A repeating decimal is a decimal fraction that eventually repeats a sequence of digits indefinitely. Let's analyze the options: A) \( 0.666666 \overline{6} \) - This notation indicates that the digit '6' repeats indefinitely. This is a repeating decimal. B) 0.123321 - This decimal does not repeat; it terminates after the digits '123321'. This is not a repeating decimal. C) 1.234545 - The digits '45' repeat indefinitely, so this is also a repeating decimal. D) \( 6.7878 \overline{88} \) - The notation indicates that '88' repeats indefinitely, making this a repeating decimal as well. From the options, both A, C, and D are repeating decimals. However, if we are to select one example, we can choose: **A) \( 0.666666 \overline{6} \)** as a clear example of a repeating decimal.