Read the following sentence. Extreme runners must be agile, strong, and skilled, not unlike other athletes; but they must also embody courage. The punctuation in the above sentence is considered grammatically correct, but it is not necessarily the best form of punctuation to use in this sentence. Which of the following would be the BEST form of punctuation to grab the reader's attention while also maintaining correct grammar?
a. Extreme runners must be agile, strong, and skilled--not unlike other athletes, but they must also embody courage.
b. Extreme runners must be agile, strong, and skilled (not unlike other athletes), but they must also embody courage.
c. Extreme runners must be agile, strong, and skilled, not unlike other athletes--but they must also embody courage.
d. Extreme runners must be agile--strong--and skilled--not unlike other athletes, but they must also embody courage.