What is the significance of the Battle of Dien Bien Phu?

Question

What is the significance of the Battle of Dien Bien Phu?

The French victory triggered an invasion by China, in support of the Viet Minh rebels.
The battle was inconclusive, and fighting between the French and the Viet Minh rebels continued for many years.
The French were defeated by the Viet Minh rebels, which marked the end of French involvement in Vietnam.
The French defeated the Viet Minh rebels, which marked the end of the communist uprising in Vietnam.

Answer 1

The French were defeated by the Viet Minh rebels, which marked the end of French involvement [and the beginning of the American involvement] in Vietnam.