Riddle

I can be the book one can never finish reading. What am I?

Choose an answer

A.A diary
B.A textbook
C.A dictionary
D.Autobiography
Hint: It's a word with 13 letters, starting with "A".

Answer

Autobiography

Why this is the answer

Just as one can never finish writing their own life story, in a sense it can also never be fully 'read' until the author's life ends.

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