20 pts HELP ME PLS !! What is the correct way to write the sentence below?

When the student council met for the last time before the winter break, they made sure to vote on whether or not to have a holiday gift drive for underprivileged children.
A.
When the student council met for the last time before the winter break, it made sure to vote on whether or not to have a holiday gift drive for underprivileged children.

B.
When the student council met for the last time before the winter break, their made sure to vote on whether or not to have a holiday gift drive for underprivileged children.

C.
When the student council met for the last time before the winter break, them made sure to vote on whether or not to have a holiday gift drive for underprivileged children.

D.
When the student council met for the last time before the winter break, he or she made sure to vote on whether or not to have a holiday gift drive for underprivileged children.