Hi,
The Lusitania was sunk in 1915 and the US did not enter the war until almost two years after the sinking. The sinking of the Lusitania and the American reaction to that sinking caused the Germans to temporarily halt their policy of unlimited submarine warfare.
Side note: Found the answer with this link :)
https://www.enotes.com/homework-help/what-impact-did-sinking-lusitania-have-what-came-418703
The battles of Lexington and Concord...
<span> C. reached the height of its power and doubled in size </span>