Which of the Following Is Not Correct

Which of the following is not correct?

A) By saving a larger portion of its GDP, a country can raise its output per worker.
B) Savers supply their money to the financial system with the expectation that they will get it back with interest at a later date.
C) Financial intermediaries are the only type of financial institution.
D) The financial system helps match people's saving with other people's borrowing.