I got a question for you: "Lean on Me" is a song written and recorded by American singer-songwriter Bill Withers. It was released in April 1972 as the first single from his second album, Still Bill. It was his first and only number one single on both the soul singles and the Billboard Hot 100. Billboard ranked it as the No. 7 song of 1972. It is ranked number 208 on Rolling Stone's list of "The 500 Greatest Songs of All Time". Numerous cover versions have been recorded, and it is one of only nine songs to have reached No. 1 in the US Singles Charts with versions recorded by two different artists.

Based on this passage, who sings the original song lean on me?
Let's think first:
To answer the question, consider the following: It was released in April 1972 as the first single from his second album, Still Bill.
Therefore, the answer is Bill Withers.