Mason was shocked to learn that the current Code is the Internal Revenue Code of 1986. He thought that U. S. tax laws change more frequently. What is wrong with Mason’s perception?

Explanation:

Based on the information provided within the question it can be said that the main misconception with Mason's perception is that Congress enacts tax legislation almost every year and this causes changes to be added to the code. Since the last huge change was in 1986, the subsequent small changes were all added into the Internal Revenue Code of 1986.