What was the purpose of the exam during wuid's rule?

It's purpose was to let people get good places in the government if they passed, but the only people that could take it were people that were already recommended into the government, so the rich and influential continued to run the government and the test was based on Confucianism.

Explanation:

Wudi was the seventh emperor of the Han dynasty of China, ruling from 141-87 BC. Wudi is the posthumous name of Emperor Wu of Han. His reign surpassed over half a century and is one of the longest reigns in Chinese history. these exams were only open to the people who were recommended fro government services already.

It ensured that those who were recommended for such exams were well aware of the Confucianism ideas. It was not open to all and only the recommended people can attend the exams under wudi rule.