Answer:
A choice.
Step-by-step explanation:
Irrational number is a number that cannot be written in a fraction form. All square roots are classified as an Irrational number unless can be evaluated to Rational number.
From A choice, you cannot evaluate the square root of 7 into any rational number. Therefore, it is an Irrational number.
B choice, even though there is a square root, but you can still evaluate from square root of 4 to 2.
For C and D, both are integers. Integers are classified to be Rational Number. Therefore, C and D both are rational.
