Into the Mist Detective Glasburry grabbed his coat and slipped silently out the door.
All around him, the London streets were filled with fog. He could barely
see several feet into the distance. Somewhere out there was the
evidence he was looking for. Just as the sun would eventually burn off
this concealing fog, so, too, would he evaporate the layers of mystery
surrounding the missing key. He smiled with pleasure as the knot of
the mystery began to unravel itself in his mind. The key, he realized,
had once been in the possession of Mrs. Amelia Melongood,
How do the authors of these two passages achieve their purposes?
A. The author of "Film Flop" convinces readers of his opinion about a
movie, while the author of "Into the Mist" entertains readers by
narrating a story
B. Both authors inform readers about the plot and characters of the
Glasburry Mystery series.

The authors of these two passages achieve their purposes in the following manner:

A. The author of "Film Flop" convinces readers of his opinion about a movie, while the author of "Into the Mist" entertains readers by narrating a story.

Explanation:

The two passages show completely different types of texts. The first passage presents the author's opinion. He talks about a certain movie, compares it to the books that gave birth to it, and concludes that the movie is a waste of time and money since it lacks depth. On the other hand, the second passage is a narrative. The author is telling us a story rather than presenting an opinion. The word choice and tone are less direct, their purpose being to describe the setting and the character's actions and thoughts vividly. With that in mind, we can safely choose letter A as the correct option:

A. The author of "Film Flop" convinces readers of his opinion about a movie, while the author of "Into the Mist" entertains readers by narrating a story.