The answer is:
Answer 2
Passive voice means you are adding too much; the sentence needs to be simpler. Let's take a look at the sentences.
1 - "Punished severely by Zeus" is a little wordy and unecessary.
2 - It is short and simple, also easy to understand.
3 - "Punished severely was Prometheus" is unecessary. Make it simpler.
4 - It is short and simple, but needs a little more detail. Who punished him?
5 - "For stealing fire and giving it to mortals" is a little extra.
