Outlook is the mailing program used to receive and send emails. The display from three columns to one column can be changed by clicking in the style's area and selecting the standard. Thus, option c is correct.
The styles area is the option in the Outlook used to change the format of how the display looks to the users in the mail area. They are found in the format text tab.
In the tab select the style's area and choose the standard option which is the one-column option that can be selected from the drop-down buttons.
Therefore, option c. choosing the standard option in the style area is used to change the display.
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