Answer:
Count
Explanation:
Let's see which function does what:
SUM
- This function totals one or more numbers in a range of cells.
COUNT
- This function gets the number of entries in a number field that is in a range or array of numbers
SQRT
- This function returns the square root of a number.
SORT
- This function sorts the contents of a range or array.
As we see, Count is the function that gets the number of entries.
