When does AP condone the serial comma?

Which is correct?
Degaussing is used for a wide and disparate variety of items including ship hulls, _______ and CRT television sets and computer monitors.
a. storage media
b. storage media,

Explanation:
Use the serial comma in this construction and enjoy — if you want to be AP-compliant, this is one of only two opportunities you’ll have.

Using the comma here helps with the clarity of the sentence so the reader understands that CRT modifies both television sets and computer monitors.

The serial comma, AKA the Oxford comma, has been one of the most passionately argued points of punctuation for many years now. We clung to it fiercely at WhatIs for a long time — years after the rest of TechTarget had gone all AP style on it. But business writing has increasingly evolved toward the simplest style possible to convey meaning and maintain readability and, inevitably, we’ve bowed to AP.

Here’s the AP ruling on the serial comma:

IN A SERIES: Use commas to separate elements in a series, but do not put a comma before the conjunction in a simple series: The flag is red, white and blue. He would nominate Tom, Dick or Harry.

Put a comma before the concluding conjunction in a series, however, if an integral element of the series requires a conjunction: I had orange juice, toast, and ham and eggs for breakfast.

Use a comma also before the concluding conjunction in a complex series of phrases: The main points to consider are whether the athletes are skillful enough to compete, whether they have the stamina to endure the training, and whether they have the proper mental attitude.

The AP Stylebook is available online.

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