单项选择题
The first ancient Olympics were held in 776 B.C.. The games got their name from Olympia, the Greek city where they took place. Like the Summer Olympics of today, the ancient Olympics were held every four years. Thousands of people from all over the Greek world came to watch. The main stadium held about 45,000 people. "We have accounts of visitors and pilgrims setting up tents all around the site," Lisa Cerrato of Tufts University said. During the first Olympics, there was only one competition — a 200-meter race. But over time the games grew to include wrestling, chariot racing boxing, and other sports. Women were not allowed to compete, but they had their own separate games. "The ancient athletes became celebrities (名人) , just like today. They often lived the rest of their lives being treated to free dinners." Cerrato said. "City-states even tried to steal away each other’s athletes by offering them various awards." The ancient Olympics existed until 393 AD. But the modern Olympics are still going strong.
How did researchers know that ancient Greeks rushed to watch the Olympics（） A．Thousands of people came to watch.
B．The main stadium is still not big enough.
C．They have found the related record of the events.
D．Many of them were visitors and pilgrims.