What is the name of the MLB championship series that determines the American League pennant winner?

Which manager won three World Series with the San Francisco Giants? Which manager led the Houston Astros to the 2022 title at age 73? What does it mean when a team "clinches" in baseball? What is the "Fall Classic"? What is a "pennant" in baseball? Which player hit three home runs in a single World Series game in both 1926 and 1928? Which Cardinals slugger hit three home runs in Game 3 of the 2011 World Series? Which catcher was known as "Pudge" and played most of his career with the Texas Rangers?