Why not D?
Suppose number of members of progressive party= 100 and each member against the bill
number of city council seats= 100 and each city council member is also against the appropriation.
Now, here we don't know number of other party member who can vote.
But for passing bills requires clear majority means more than 50% votes.
A says progress party holds majority seats on city council.
means more than 50 members of progress party were also member of city council.
now total members of progress party and city council may be more than 150.
Considering this, we can not say that bill will be passed or not because still we don't know numbers of members of other parties.
But D clearly says that 75% votes cast against the appropriation were belong to progress party. and all votes of proress party is against the bill. Therefore, bill will be rejected.
Where I am wrong.