hired burglars to break in to the Watergate complex, which was home to . A Nixon administration official named testified that the president knew about the break-in. Soon after, another official testified that a was located in the Oval Office.

The burglars broke into the Democratic National Committee offices in the Watergate complex. Nixon administration official John Dean testified that President Nixon knew about the break-in; later, Alexander Butterfield revealed that a recording system was installed in the Oval Office. So the correct choice is John Dean.

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