The correct answer is: A. Graciously, the audience rose up and applauded the guest speaker.
The original sentence: "The audience rose up and graciously applauded the guest speaker with a standing ovation" contains redundancies and wordiness, because, if you use the words, "standing ovation", you do not need to additionally say that "...the audience rose up...", since a standing ovation already implies that the audience stood up. Option A, is the best option because it eliminates the aforementioned redundancy, and is also grammatically correct. The remaining options are either grammatically incorrect or have poor syntax.