Who adopted Superman as per the passage?

Context: Superman was born on the fictional planet Krypton and was named Kal-El. When he was a baby, his parents sent him to Earth in a small spaceship moments before Krypton was destroyed in a natural cataclysm. His ship landed in the American countryside, near the fictional town of Smallville. He was found and adopted by farmers Jonathan and Martha Kent, who named him Clark Kent. Clark developed various superhuman abilities, such as incredible strength and impervious skin. His adoptive parents advised him to use his abilities for the benefit of humanity, and he decided to fight crime. To protect his personal life, he changes into a colorful costume and uses the alias "Superman" when fighting crime. Clark resides in the fictional American city of Metropolis, where he works as a journalist for the Daily Planet. Superman's supporting characters include his love interest and fellow journalist Lois Lane, Daily Planet photographer Jimmy Olsen and editor-in-chief Perry White, and enemies such as Brainiac, General Zod, and his archenemy Lex Luthor.

Answer: Jonathan and Martha Kent