Brain Test Level 91 Answer
Hunting through the objects in the scene for a stray letter L to drag into the gap. There is no spare letter anywhere in the picture, because the one you need is not part of the picture.
The puzzle
Complete the word 'leve_'.
The answer
Drag the letter L from the word 'Level' in the counter at the top of the screen down into the blank.
What most people try first
Hunting through the objects in the scene for a stray letter L to drag into the gap.
Why that is the answer
There is no spare letter anywhere in the picture, because the one you need is not part of the picture. The level counter at the top of the screen reads Level, and its L can be dragged down into the blank like any other object. The game treats its own interface as part of the playing field, and this is the level that teaches you to look there.
If your level 91 looks different
Unico Studio shuffles level numbers between game versions and platforms, so the puzzle on your screen may carry a different number from the one here. If the question above is not the one you are looking at, the full levels 51 to 100 walkthrough lists every puzzle in this stretch by its question, which is easier to match than a number.