The right answer is C) =SUM(A10:E10)
This is a problem of using Excel. This problem has been solved in Figure 1 and 2. The first formula =SUM($A1:C1) has been written in cell D1. This sum is:
Cell A1 + Cell B1 + Cell C1
Next, by using copy and paste tool in cell F10 the formula automatically changes to =SUM(A10:E10). This means that the program will compute the following sum:
Cell A10 + Cell B10 + Cell C10 + Cell D10 + Cell E10