Which alphabet letter is a question?

Many have heard it, but nobody has ever seen it, and it will not speak back until spoken to. What is it?

Rebus Puzzle Definition: A rebus is an illusion device that uses pictures to represent words or parts of words.
What does This Rebus Puzzle Identify?

How many triangles can you count in the figure given?

A man is lying dead in a field where no one is around. His head is split open and his legs are disfigured. Near to him, there is an unopened package. No living organism can be found anywhere at the crime scene.

How did he die?

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

A chess tournament is taking place on knock-out terms (the one who loses the match is out of the game).
(a) If 10 matches are played in total, how many players participated?
(b) If 20 players took part in the tournament, how many matches were played?

There was a greenhouse.
Inside the greenhouse, there is a white house.
Inside the white house, there is a red house.
Inside the red house, there are lots of babies.

What is It?

A bomb exploded in a room full of married couples and no one died. How?

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?