The probability of getting a <em>country CD</em> out of all the CDs is the number of <em>country CDs</em> divided by the <em>total number of CDs</em> in Dante's Collection.
The <em>total number of CDs</em> in Dante's collection is .
The total number of <em>country CDs</em> is 12.
So our required probability is .
In percentage this is 3 divided by 10, and then multiply by 100. We get 30%. Answer choice D is correct.