What caused the start of the iran-iraq war in 1980

Iraq invaded Iran on 22 September 1980, triggering a bitter eight-year war which destabilised the region and devastated both countries. The then Iraqi leader Saddam Hussein claimed as a reason for the invasion a territorial dispute over the Shatt al-Arab, the waterway which forms the boundary between the two countries.

Explanation:

I believe the answer is: it can decrease inflation

Contractionary monetary policy refers to the economic policy that is aimed to decrease the money supply that circulated in the market.
When the amount of money is decreased, it's rarity cause that specific currency to increase in value, which would lead to the decrease in inflation