For example, take an even number like $\displaystyle 2$ and an odd number like $\displaystyle 5$. Their product is $\displaystyle 10$ which is an even number. No matter what examples we use; we will find that the answer is always even. Furthermore, it can never be a square number because the multiplicand and multiplier will be two different numbers (one odd and one even).

Even though it's a radical, we can simplify$\displaystyle \sqrt{16}$.

$\displaystyle \sqrt{16}=4$

Check the answer.

$\displaystyle 4*4=16$

The answer is $\displaystyle 4$. 

$\displaystyle 4$ is an integer and a composite number with factors of $\displaystyle 1, 2, 4$. Furthermore, it can be expressed a rational number $\displaystyle (4=\frac{4}{1})$.

Thus, the final answer is I, III, V.

Square numbers have one factor. If that factor is multiplied by itself, then the number becomes a perfect square. The only number in the selection that meets this requirement is $\displaystyle 121$. We can multiply $\displaystyle 11$ twice to get the perfect square $\displaystyle 121$. 

In order to determine if a number is odd, we will check the ones digit. It must contain $\displaystyle 1$, $\displaystyle 3$, $\displaystyle 5$, $\displaystyle 7$, or $\displaystyle 9$. The answer is integers that have a ones digit that ends in $\displaystyle 1$, $\displaystyle 3$, $\displaystyle 5$, $\displaystyle 7$, or $\displaystyle 9$. 

Whole numbers start from $\displaystyle 0$ and include all positive integers. On the other hand, natural numbers are all positive integers that we can count starting from $\displaystyle 1$. The only difference is that $\displaystyle 0$ is found in whole numbers but not in the natural numbers series. Thus, $\displaystyle 0$ is the correct answer. 

Odd numbers are integers that have a ones digit that ends in $\displaystyle 1$, $\displaystyle 3$, $\displaystyle 5$, $\displaystyle 7$, or $\displaystyle 9$. Choices II, III, V  are odd numbers because they have a ones digit of $\displaystyle 3$, $\displaystyle 1$, and $\displaystyle 9$ respectively. 

When you take two prime numbers, you are creating a composite number. A compositie number has at least one more factor than one and itself. Since you multiply two prime numbers, you are increasing the factors of the new number. 

For example, we can take the negative integers $\displaystyle -10$ and $\displaystyle -5$. When we divide $\displaystyle \frac{-10}{-5}$, we get an answer of $\displaystyle 2$. This is an integer and a rational number. However, if we reverse it $\displaystyle \frac{-5}{-10}$, we get an answer of $\displaystyle \frac{1}{2}$. This is not an integer but it is a rational number. Integers can be rational numbers as they are expressed as any number over one. Futhermore, rational numbers are defined as the expression of any quotient or fraction possessing a non-zero denominator. Thus, our answer is rational numbers. 

A whole number is any number without a fraction or decimal, but negative numbers are NOT whole numbers. Therefore, the only correct choices from this set are $\displaystyle 2$ and $\displaystyle 15$, which are neither negative nor have decimals. 

Negative numbers are integers, they are real, and they are rational. Natural numbers, by definition, are whole and non-negative numbers. Therefore, $\displaystyle -3$ is NOT a natural number.