Consider the question. "The First Cut Is the Deepest" is a 1967 song written by Cat Stevens, originally released by P.P. Arnold in May 1967. Stevens' own version originally appeared on his album New Masters in December 1967.

Answer this question based on the passage: who sang the first cut is the deepest originally?
What is the step-by-step reasoning process to arrive at the answer: P.P. Arnold?
The relevant information is: "The First Cut Is the Deepest" is a 1967 song written by Cat Stevens, originally released by P.P. Arnold in May 1967.