Which paragraph effectively utilizes the most variety of sentence structures?

A) The term earworm is a translation of the German word ohrwurm. Other common names for the condition include “stuck song syndrome” and “melodymania.” The problem with these annoyingly catchy songs is that no one knows why they become stuck in our heads.
B) Kellaris’s Theory of Cognitive Itch (2001) compares earworms to histamines that can cause your skin to itch. Kellaris believes that exposure to certain types of music can cause an itch inside our brains, and the only way to scratch it is to repeat the music in our minds over and over again. The professor may have scientific evidence to back up his claim.
C) There is no known cure for earworms. Many people try to listen to other music or think about something else to get the offending song out of their heads. An earworm usually lasts a few hours, but some people have reported symptoms lasting for nearly a week. Until someone isolates a cause, researchers in the marketing and neurological fields will continue to study the various elements of this fascinating phenomenon.
D) A study conducted at the University of Cincinnati found that ninety-eight percent of all people are afflicted with earworms at some point in their lives. Don’t rush off to your physician or start checking your ears just yet—earworms aren’t creatures, they’re songs.
Marketing professor and leading earworm researcher James Kellaris studies the way that music influences consumers. Kellaris defines an earworm as any song, tune, or commercial jingle that worms its way into your head and repeats itself involuntarily. After a while, a merely catchy song can become extremely annoying and distracting to the afflicted person, causing them to lose focus on the job or at school.