Question: Who has the most strikeouts in a career?
Disambiguated questions and answers: question: What MLB pitcher has the most strikeouts in a career?
What MLB batter has the most strikeouts in a career?
What NCAA Division I softball pitcher has the most strikeouts in a career?
answer: Nolan Ryan
Reggie Jackson
Monica Abbott
Natural Questions answer: Nolan Ryan (from the Wikipedia article "List of Major League Baseball career strikeout leaders")