World Central Banks Act as EU Growth Stalls

The European Central Bank (ECB), along with its U.S., Japanese, Swiss, and British counterparts, announce they would inject extra U.S. dollar liquidity into banks facing a shortage of the U.S. dollars. European bank shares have plunged over the past weeks as their usual sources of U.S. dollars have dried up on concerns they might be hit by a Greek debt default, and the announcement sparked a strong bank and general stocks rally.

Source: AFP, September 15, 2011

How can a group of central banks "inject extra dollar liquidity"? What will such an action do to the quantity of U.S. dollars in Europe?

Such an action will _______ the quantity of U.S. dollars in Europe.

A.

not change

B.

decrease

C.

increase