Which decision by the Federal Open Market Committee affects the entire financial world?

There are two major actions the Federal Open Market Committee executes that can affect the entire financial world.

The first one is the modification of the interest rates and the second is the issuing of new money.

Explanation:

The reasons behind this answer are that the modification of interest rates affects the whole world as it affects investments and debt. Therefore if they are moved up or down, the world will react to this movement because the dollar U. S. dollar and its economy has strong relations with the whole world. Second, the issuing of new money changes the value of the dollar and so it affects the rest of the world because the devices get stronger or weaker against it.