Who is revealed to be the heir of Slytherin in Harry Potter and the Chamber of Secrets?

In Harry Potter and the Chamber of Secrets, it is revealed that Tom Riddle, the young version of Lord Voldemort, is the heir of Slytherin. Riddle, a direct descendant of Salazar Slytherin through his mother, Merope Gaunt, inherited the ability to speak Parseltongue, allowing him to control the Basilisk hidden in the Chamber of Secrets. His goal was to rid Hogwarts of Muggle-born students, fulfilling Slytherin’s original vision for the school. Riddle’s diary, an early Horcrux, preserved his 16-year-old self, manipulating Ginny Weasley into reopening the Chamber and unleashing the Basilisk.