Explanation:

Steffi Graf, the German tennis legend, was the first athlete to achieve a "Career Golden Slam" in tennis. Graf accomplished this remarkable feat by winning all four Grand Slam singles titles (Australian Open, French Open, Wimbledon, and US Open) along with an Olympic gold medal in singles tennis. Her unparalleled success and dominance in women's tennis during the late 1980s and early 1990s solidified her legacy as one of the greatest tennis players of all time.