What does this rebus mean?

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There are three light switches outside a room. One of the switches is connected to a light bulb inside the room.
Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb?

Can you find the thief by just looking at the picture below?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

You see me once in June, twice in November, and not at all in May. What am I?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

Can you find out the total number of triangles in the given figure?

What has a bottom at the top?

Cristina leaves home and then she makes exactly 3 left turns and returns home where she found 2 girls wearing the mask.

Who are these two masked girls?

A man is looking at a photograph of someone. His friend asks who it is. The man replies, “Brothers and sisters, I have none. But that man’s father is my father’s son.” Who was in the photograph?