I got a question for you: In the history of the Triple Crown, 13 horses have won all three races: Sir Barton (1919), Gallant Fox (1930), Omaha (1935), War Admiral (1937), Whirlaway (1941), Count Fleet (1943), Assault (1946), Citation (1948), Secretariat (1973), Seattle Slew (1977), Affirmed (1978), American Pharoah (2015), and Justify (2018). As of 2018, American Pharoah and Justify are the only living Triple Crown winners.

Answer this question: who was the last horse who won the triple crown?
Let's think first:

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
The important part for answering this question is: In the history of the Triple Crown, 13 horses have won all three races: Sir Barton (1919), Gallant Fox (1930), Omaha (1935), War Admiral (1937), Whirlaway (1941), Count Fleet (1943), Assault (1946), Citation (1948), Secretariat (1973), Seattle Slew (1977), Affirmed (1978), American Pharoah (2015), and Justify (2018).
Therefore, the answer is Justify.