Introduction:
Rational numbers are a subset of real numbers which can be expressed in the form of p/q where p and q are integers and q is not equal to zero.

Zero as a Rational Number:
Zero is a rational number because it can be expressed as 0/1, where 0 is an integer and 1 is also an integer which is not equal to zero.

Explanation:
To understand why 0 is a rational number, we need to understand the definition of a rational number. Rational numbers are those numbers which can be expressed in the form of p/q, where p and q are integers and q is not equal to zero.

When we take the case of zero, we can write it as 0/1, where 0 is an integer and 1 is also an integer which is not equal to zero. Therefore, we can conclude that zero is a rational number.

Conclusion:
In conclusion, zero is a rational number because it satisfies the definition of a rational number, which is a number that can be expressed in the form of p/q, where p and q are integers and q is not equal to zero.

Zero is a rational number. We know that the integer 0 can be written in any one of the following forms. For example, 0/1, 0/-1, 0/2, 0/-2, 0/3, 0/-3, 0/4, 0/-4 etc.