Final answer:
The number that produces a rational number when added to 0.6 is 5/7.
Step-by-step explanation:
To find the number that produces a rational number when added to 0.6, we need to understand what a rational number is. A rational number is any number that can be written as a fraction, where the numerator and denominator are both integers. We can see that option B) 5/7 is a rational number, so it must be the answer.