Riddle

As your ideas grow, I shrink. What am I?

Choose an answer

A.A budget
B.Confidence
C.A deadline
D.Pencil
Hint: It's a word with 6 letters, starting with "P".

Answer

Pencil

Why this is the answer

A pencil physically gets shorter (from sharpening and writing) the more ideas and words you put down on paper.

This riddle is filed under "What Am I?" Riddles and rated Medium.