The picture doesn’t work for me, so I took a guess of what should be on there.
The J value corresponds to: J=L+S.
If there are three energy levels and thus three values for J, the lowest value should correspond to the case where L and S are oriented parallel and opposite.
The highest value should correspond to the case where L and S are oriented parallel and in the same direction.
And the middle value should correspond to the case where L and S are perpendicular.