The answer to the first blank is C. It is important for a speaker to understand the needs of the audience because it helps the speaker to hone their message for the audience. Understanding the audience will give you the idea of what your audience is like then you can adjust yourself accordingly so that you can approach to them easily and you can be understood by them. The answer to the second blank is B. Writers should avoid jargon because jargon limits what ideas can be explored. If a writer uses jargons, he wouldn't be able to write much because jargons are easily understood by people and there will be no need of further explanation.
