This is the 6067th most frequent Korean word.
선택했다고
"선택했다고" means "chose" or "decided" in English.
선택을 했다 indicates that a choice was made.
그는 어떤 선택을 했다고 말했습니다.
He said he made a choice.
선택했다고 indicates that the action of choice is being reported.
내가 이 책을 선택했다고 너에게 전해줄게.
I'll let you know that I chose this book.
선택했다고 suggests that the act of choosing is being described or recounted.