Answer: D) Real, Rational
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Step-by-step explanation:
In your studies so far, every number you encounter is a real number. This changes when your teacher will introduce complex and imaginary numbers later on down the road. So 3.5 is a real number. A real number is essentially any number we can express as a decimal value (whether the decimal terminates, or goes on forever).
The number 3.5 is also rational because we can express it as a ratio of two integers, aka a fraction of two integers. Specifically, we can say 3.5 = 35/10 = 7/2.
The number 3.5 being rational would automatically rule out "irrational", since "irrational" means "not rational". The number 3.5 isn't an integer either. It would need to be either a positive whole number, negative whole number, or zero for it to be an integer. We rule out "natural number" for similar reasoning that we ruled out "integer".