The sum of all two digit numbers is

The correct answer is (d) 4920.

To find the sum of all two-digit numbers, we can use the following formula:

$S = \dfrac{(100 + 99)}{2} \cdot 99 = 4920$

where $S$ is the sum of all two-digit numbers, and $100$ and $99$ are the first and last two-digit numbers, respectively.

Option (a) is incorrect because it is the sum of all one-digit numbers.

Option (b) is incorrect because it is the sum of all three-digit numbers.

Option (c) is incorrect because it is the sum of all four-digit numbers.