Final answer:
The main skills that contribute to effective synthesizing are quoting, paraphrasing, summarizing, and analyzing. The skill that does not contribute to effective synthesizing is proofreading.
Step-by-step explanation:
The main skills that contribute to effective synthesizing are quoting, paraphrasing, summarizing, and analyzing. Therefore, the correct answer is b) Proofreading. Although proofreading is an essential skill for writing, it is not directly related to the process of synthesizing information from various sources. Synthesizing involves combining information from different sources and making connections to create a new understanding. This skill requires the ability to summarize, paraphrase, and quote effectively to support your ideas.