阅读下列短文，从每题所给的四个选项(A、B、C和D)中，选出最佳选项。并在答题卡上将该项涂黑。
A
Studying for an exam while listening to music is not smart, because background music can injure your ability to perform memory tasks, new research has found.
Study participants were asked to recall a list of eight consonants (辅音字母) in the order they were presented. They did this while in five different sound environments: quiet surroundings; music they liked~ music they disliked; changing state; and steady state.
The participants recall ability was poorest when listening to music, regardless of whether
they liked or disliked it, and in changing-state conditions. The most accurate recall occurred
when participants performed the task in steady-state environments, according to the stud
