Detailed Instructions: In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.
Q: Eight men and ten women have won Career Grand Slams in singles play (rows one and two); among them two men and five women have at least two Career Grand Slams in singles (column three). Since the beginning of the open era, five men and six women have achieved this (Rod Laver, Andre Agassi, Roger Federer, Rafael Nadal, Novak Djokovic; Margaret Court, Chris Evert, Martina Navratilova, Steffi Graf, Serena Williams and Maria Sharapova).
A:
who has won a career grand slam in tennis