<p>I would go with A since those refers to the skills, and it makes the sentence much more clear. A sounds more redundant but it makes more sense , whereas E doesnt tell us what exactly is less complex.
Whats the answer?</p>
<p>Two issues here:
1) Parallelism: SAT Writing testers are fanatical about it, especially in comparisons. Ensuring parallelism can lead to slightly awkward phrasing. Here you need a term that is parallel with skills. I'm guessing A is right, because it fills the need for parallelism with the word "those."
2) Gerunds vs. infinitives: I think you're ok on this one, based on the way you've narrowed down the choices, but the SAT Writing testers are also big on this issue. Depending on the part of the country where you live, the preferred choice may be automatic to you, or you may feel that both should be equally acceptable. To obtain background information on this, google the words
infinitive gerund
and you will find several sites right near the top of the list that provide very helpful information (This distinguishes A vs. B, C vs. E)</p>
<p>liebenasuka, yes, that works, too :)
I raised the gerund vs. infinitive issue, even though the OP seems to have no problem with it, because it is a recurring "motif" in the SAT writing questions (beyond idiomatic preposition choices).</p>
<p>The gerund is a verbal noun, ending in "ing." (The same word is used to form the present progressive tense.)
The infinitive is the verb form with "to xxx."
In some cases, either is acceptable, but in other cases, one form is preferred.</p>
<p>Most of the gerund vs. infinitive questions are actually set up to catch non-native speakers. However, there are a few that are tricky even for native English speakers. </p>
<p>On the ego4u web site, try taking a look at the "use" sections. (You probably won't find the tests worthwhile.)</p>