Mirror type. This is explained in the video. The basic idea is that each letter has a partner which is a mirror image of itself.

eg A and Z (1 from start and 1 from end of alphabet)

    B and Y(2 from start and 2 from end of alphabet)

    C and X (3 from start and 3 from end of alphabet)

etc

LEARN THESE PAIRS! Then you will spot these questions types immediately and not waste time using the normal method.