Which sentence below is correctly punctuated?

a. Richard Bushnell, who attended the University of Utah, enjoyed playing computer games in college.
b. Bushnell hired Steve Jobs who later become the CEO of Apple Computers.
c. The version of Pong, that the Atari introduced, was extremely popular.

a. Richard Bushnell, who attended the University of Utah, enjoyed playing computer games in college.

The correct sentence is:

a. Richard Bushnell, who attended the University of Utah, enjoyed playing computer games in college.

To determine which sentence is correctly punctuated, we'll need to analyze each sentence and its punctuation. Here's how to evaluate them:

a. Richard Bushnell, who attended the University of Utah, enjoyed playing computer games in college.
- This sentence is punctuated correctly. The phrase "who attended the University of Utah" is enclosed by commas, which is the appropriate punctuation for a nonrestrictive clause providing additional information.

b. Bushnell hired Steve Jobs who later become the CEO of Apple Computers.
- This sentence has incorrect punctuation. It needs a comma after "Jobs" to separate the nonrestrictive clause "who later become the CEO of Apple Computers." The correct version would be: "Bushnell hired Steve Jobs, who later become the CEO of Apple Computers."

c. The version of Pong, that the Atari introduced, was extremely popular.
- This sentence also has incorrect punctuation. The comma before "that" should be removed. The correct version would be: "The version of Pong that the Atari introduced was extremely popular."

In conclusion, the correctly punctuated sentence is option a: "Richard Bushnell, who attended the University of Utah, enjoyed playing computer games in college."