一道gmat题Most North Carolina ski resorts broadcast music onto

一道gmat题
Most North Carolina ski resorts broadcast music onto the slopes; skiers can choose among hard rock, soft pop, and “beautiful music” slopes, there are no slopes without music.
(A) skiers can choose among hard rock, soft pop, and “beautiful music” slopes, there are
(B) because skiers can choose hard rock, soft pop, or “beautiful music,” there are
(C) however, skiers can choose among hard rock, soft pop, “beautiful music,” and
(D) although skiers can choose among hard rock, soft pop, and “beautiful music” slopes, there are
(E) skiers can choose among hard rock, soft pop, “beautiful music” slopes, but
为什么是D不是E?不是说有there be结构的都不正确的吗?
谢谢!
划线部分skiers can choose among hard rock, soft pop, and “beautiful music” slopes, there are