The true statement about the relationships between the number sets is:
All integers are also rational numbers.
This is because rational numbers are defined as numbers that can be expressed as the quotient of two integers, where the denominator is not zero. Every integer can be expressed as a fraction (for example, the integer 5 can be written as 5/1), which makes them rational numbers.
The other statements are false:
- Not all natural numbers are real numbers: False, as all natural numbers are indeed real numbers.
- Whole numbers include all positive and negative integers: False, as whole numbers include only non-negative integers (0 and positive integers).
- Some irrational numbers are also integers: False, as irrational numbers cannot be expressed as fractions, so they cannot be integers.