Is it correct parallel structure. Incorrect parallel structure

Select the rebuttal statement that best refutes the viewpoint in section one. a) it is necessary to oversee the athletes involved in mixed martial arts. b) it is unnecessary to oversee the athletes involved in mixed martial arts. c) it is necessary for athletes involved in mixed martial arts to self-regulate. d) one distinctive feature of mixed martial arts is the combination of various techniques.

Is the sentence the refree blew her whistle and both teams rushed onto the field a coumpound or simple sentence

The bus driver who, only works weekdays, always waits for me when i'm running latecorrect the comma sandwich