Right answer:
c) sabéis
The correct answer is sabéis (the option has a little mistake) because the subject pronoun is vosotros, hence sabéis matches this subject pronoun. On the other hand, sabéis comes from the verb saber and is conjugated in the simple present. Vosotros means you all. Finally:
Vosotros sabéis crear presentaciones en la computadora (You all know how to create slides on the computer)
