Answer:
A). tri-
Explanation:
As we know that here in the given compound we have one sulfur and three oxygen atoms.
So here in this nomenclature we can say that
one = mono
two = di
three = tri
five = penta
so above are the different prefix which we will use in different cases when atoms are arranged in different numbers.
Since we have three atoms here for oxygen so the prefix must be "tri" here in this case