In Microsoft Excel, to move an entire column from one location to another, you must use the Shift key in conjunction with dragging. First, select the entire column you wish to move. Then, position your mouse cursor over the border of the selected column until it changes into a four-headed arrow. While holding down the Shift key, click and drag the column to its new desired position. Releasing the mouse button and then the Shift key will insert the column into the new spot, shifting existing columns to accommodate it.
Using the Ctrl key while dragging a selected column would copy the column instead of moving it. The Alt key is typically used for accessing ribbon shortcuts or specific functions in combination with other keys, but not for this drag-and-drop column movement. The Tab key is used for navigating between cells to the right or between fields in a dialog box, not for manipulating entire columns. Thus, Shift is the correct key for moving columns.