The following questions present a sentence, part of which or all of which is underlined. Beneath the sentence, you will find five ways of phrasing the underlined part. The first of these repeats the original; the other four are different. If you think the original is best, choose the first answer; otherwise choose one of the others.
These questions test correctness and effectiveness of expression. In choosing your answer, follow the requirements of standard written English; that is, pay attention to grammar, choice of words, and sentence construction. Choose the answer that produces the most effective sentence; this answer should be clear and exact, without awkwardness, ambiguity, redundancy, or grammatical error.
To be a great salesman requires p personal skills, the ability to think fast, and demands a can-do attitude.（）
A. requires p personal skills, the ability to think fast, and demands
B. requires p personal skills, the ability to think fast, and
C. requires p personal skills, demands the ability to think fast, and
D. requiring p personal skill, an ability to think fast, and demands
E. demands p personal skills, an ability to think fast, but with
