Although coal, hydrocarbons, iron ore, platinum, copper, chromium, nickel, gold and other minerals have been found, they have not been in large enough quantities to exploit. The 1991 Protocol on Environmental Protection to the Antarctic Treaty also restricts a struggle for resources.
Hm, are you sure you got the question right? Because all of the sentences are written in active voice! Active voice is essentially everything that is not in the passive voice, and I don't see any passive voice here.
Passive voice would be formed with subject+form of "to be" + past participle,
and we have no example of this. All of the sentences here are in active voice.
Answer:
The word maleficent means causing harm especially by supernatural means, and we can determine this because the root 'mal' means evil as stated, and maleficent is a term used for evil occurences (specifically in movies and stuff)
Explanation:
So you can determine that the adjective describes something evil or bad because of the use of the root :) Sorry if this isn't specific enough, but it's quite straight forward to me at least so I don't know how to elaborate if you need a more formal answer