Which boolean operator decreases the number of references by requiring a search to contain both of the words or phrases desired?

Examine the dates in this timeline: • 1918: the ottoman empire loses control of iraq to the britishfollowing world war i.• 1932: the kingdom of iraq is granted its independence from greatbritain• 1945: mustafa barzani leads a failed rebellion against the iraqigovernment• 1948: the al-wathbah uprising results in protests against the iraqigovernment before it is violently suppressed.• 1958: the kingdom of iraq is overthrown by military leaders whoestablish the republic of iraq,• 1980: iraq invades iran, launching the iran iraq war.• 1990: iraq invades kuwait but is defeated by united nations forcesled by the united states.• 2003: the united states and its allies invade iraq and remove itsdictator, saddam hussein.which title would best suit the period in iraqi history from 1980 through1990? a. the era of political instability and protestb. the era of american involvementc. the era of iraqi aggressiond. the era of early iraqi independence