its rational - 5.78 = 5.787878.
D.
Step-by-step explanation:
We have been given a number 5.78. We are asked to choose the correct statement which shows that 5.78 is a rational number.
Upon looking at our given choices, we can see that only option A is the correct choice as it has repeating digits (78) after decimal.
We know that a number with repeating decimals can be written as a fraction, therefore, option D is the correct choice.