​Which of the following is INCORRECT? ​

Correct option is C

Solution:

Option A: True. The number 1 is the multiplicative identity for rational numbers since multiplying any rational number by 1 does not change its value.

Option B: True. The commutative property holds for natural numbers under addition (e.g., $2+3=3+2$).

Option C: Incorrect. Not every rational number is a whole number.

For example, $$\frac {1}{2}$$​ is a rational number but not a whole number.

Option D: True. The reciprocal of 1 is indeed 1. ( since,  11=1 \frac{1}{1} = 1$$\frac {1}{1}$$​=1   )

The Incorrect option is C: Every rational number is a whole number.

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