The prefix used in a word to indicate opposite of, is ill. For example, illiterate
There were several problems that the Church faced during
this period. There was the Black Death
which ravaged Europe and caused the deaths of thousands of people. There was the transfer of the Papal Seat from
Italy to Avignon, France that gave an indication that the French now had power
of over the Papal Seat. This led to
elections of various popes known as the Great Schism where there was now
conflict within the Church.
C is correct i believe. its not A because that could not be a sentance byitself, not b because im sure you know why and d might be but then the teacher would be trying to explain to you something other then the rules of punctuation