Charles Spurgeon Commentary 1 Chronicles 21:9-11

"And Jehovah spake unto Gad, David`s seer, saying, Go and speak unto David, saying, Thus saith Jehovah, I offer thee three things: choose thee one of them, that I may do it unto thee. So Gad came to David, and said unto him, Thus saith Jehovah, Take which thou wilt:" — 1 Chronicles 21:9-11 (ASV)

And the LORD spoke to Gad, David's seer, saying, Go and tell David, saying, Thus says the LORD, I offer you three things: choose you one of them, that I may do it to you. So Gad came to David, and said to him, Thus says the LORD, Choose you–

One of them, that I may do it to you. David was to choose where there was no choice, for everything proposed to him seemed to be equally bitter.