Final answer:
Angkor Wat is the major Khmer monument dedicated to Buddhist beliefs.
Step-by-step explanation:
The major Khmer monument that is dedicated to Buddhist beliefs is Angkor Wat. Initially, Angkor Wat was a Hindu site dedicated to Vishnu, but it was later converted into a Buddhist site.
The temple complex, built by the kings of the Khmer Kingdom between 1113 and 1150, showcases Khmer architecture and is a symbol of Cambodia today.