The correct answer to this question is false.
The number 0.8 can in fact be written as 8/10 (because when you divide 8/10 you get 0.8 so they are equivalent values); however, rational numbers are those that can be written as a fraction (the division of two numbers). Irrational numbers are numbers that cannot be expressed in fractional form. This means that 8/10 is not irrational, it is rational, because you can express it in fractional form. This means your answer is false.
Hope this helps!