Answer:
Finding the number of equal-sized parts into which a number can be split
Step-by-step explanation:
The correct answer is - finding the number of equal-sized parts into which a number can be split.
Division is defined as the action of splitting something in equal parts.
So, here the first option states this definition.
Taking an example of: Lets divide 100 in 5 equal parts. So, this becomes
This can be also written like : 
So, division is where you split something equally.