茫然！

Most insomnia is not an illness or a physical condition so much as a symptom of another problem that may simply be a reaction to certain medications, anxiety about travel, or stress before a job interview.

1. an illness or a physical condition so much as a symptom of another problem that may simply be a reaction to certain medications
2. an illness or a physical condition so much as symptomatic of another problem that may be a simple one, like a reaction caused by certain medications
3. so much an illness or a physical condition but a symptom of another problem that may be as simple as when certain medications cause a reaction
4. so much an illness or a physical condition, but it is a symptom of another problem, maybe a simple one like certain medications causing a reaction
5. so much an illness or a physical condition but symptomatic of another problem, maybe simply a reaction to certain medications

GWD给出的答案是E，茫然！maybe不是口语化的词吗？而且symptomatic 是个形容词，怎么？？

我的答案是C

c中 as simple as when certain medications cause a reaction，……

as as 比较结构，但显然simple词和后面句子无法比较，相比之下，只能选d。