Search a column for highest value, return matching cell reference in column A

In this example, the goal is to use =MAX and an IF formula to search Column C for the highest numerical value, and then return the contents of a cell in Column A in the same row as the highest numerical value in Column C in the cell marked with an ?. In this case, cell C2 would have the highest numerical value, so 'DEF' would be displayed in place of the ?.