Excel 2007 : Looking for formula that links corresponding column data.

[wbsc56]

I'm trying to find a formula that places a value (actually text in a given cell) into that new cell (B20), this value(text) can and will change depending on what the value of the cell next to it (C20) is. This value in (C20) changes but the value given will always be in the range of cells above it (C2:C17). Same with (B20), it too will be represented by a range of cells above it (B2:B17). To top things off the formula in cell (C20) is the following, =LARGE($C$2:$C$17,1). So how do i get get B20 to correspond to C20 based on their locations in the given ranges?