Riddle

What gets whiter the dirtier that it gets?

Choose an answer

A.A shirt
B.A car
C.A window
D.A chalkboard.
Hint: It's a 2-word phrase with 11 letters, starting with "A".

Answer

A chalkboard.

Why this is the answer

A chalkboard (blackboard) accumulates white chalk dust and marks the more it's used, so the 'dirtier' it gets, the whiter it appears.

This riddle is filed under Dirty, Family Riddles and rated Easy.