Cutter, why do I get the feeling you are cheating somehow?

I see it targeting two columns, both B and C. I raced to look up the INDEX() function and this response really confuses me. From what I understand, INDEX returns the value of [row, col] within the specified range, for example: INDEX(B2:C4, 1, 1) would return 1 since "1" is in the first row and column of the range B2:C4

What is this sorcery