How could the Bank of Canada decrease the money supply?

Question

Quizplus · Accepted Answer

If the Bank of Canada increases the bank rate, it makes borrowing more expensive for commercial banks. This reduces their ability to offer loans to consumers and businesses, which decreases the overall money supply in the economy. A and C would both increase the money supply as the Bank of Canada would be injecting money into the economy by buying government bonds or lowering the reserve requirement for banks. B is not a feasible option as decreasing the bank rate would encourage more lending and therefore increase the money supply.

How Could the Bank of Canada Decrease the Money Supply