Unique Rectangle Type 3
Use solution uniqueness to combine a rectangle's extra candidates with nearby cells into a subset that yields eliminations.
All candidates have been entered in the empty cells.
Assume that the puzzle has a unique solution. Filling the four cells with only two digits lets those digits swap into another solution. Therefore, at least one extra candidate 2 and 5 in A is true. A and B then contain the same number of cells and candidate digits. Candidates 2 and 5 marked × can be removed.