In order to keep the cell reference the same, the formula to be used should be $E$19.
B. $E$19
Explanation:
The concept of relative and absolute cell reference has been used here. By default, the spreadsheet software uses the relative cell referencing.
But if a user wants to keep a cell or a column or both of them constant, it can be achieved with the help of absolute cell referencing by using the dollar sign ahead of the component to be kept constant.
In the given question, the cell has to be kept constant so the dollar sign would be used ahead of both the row and column.
