Which is the fastest way to make many formatting changes to a range of cells? a. select each cell, right-click, use the ribbon to make changes b. select the range, right-click, use the ribbon to make changes c. select the range, right-click, format cells, make changes d. select each cell, right-click, format cells, make changes

For formatting, Answer is C.

C. select the range, right-click, format cells, make changes

After selecting the range you have all options to make Formatting changes on the Cells and values in the cell.
For Formatting
By navigating on different tabs depending on the requirement (e.g. go to home tab and find under styles (format cells etc.)
By navigating on condifional formatting depending on the value you can assign simple conditions to change the format

For Values
By navigating on data tab you can also manipulate the values