'That now prevail',is it an adjective or an adverb

invention of the washing machine

in the past, people used sticks and stones or scrub boards to clean their clothing. as it was sweaty, backbreaking work, we owe a world of to james king because he created the model for the modern washing machine in 1851. the most important issue was that this machine cleaned clothes while a person cranked the handle. doing this made people who used it develop strong muscles in their arms. later, in 1908, alva j. fisher created an electric washing machine named thor. this one was not the first automatic washing machine. however, it was one of the most popular models at the time.

harlem's  cotton club boasted the talents of duke ellington. singers such as bessie smith and billie holiday popularized blues and jazz vocals. jelly roll morton and louis armstrong drew huge audiences as white americans as well as african americans caught jazz fever.

the correct answer is:   [d]:   " diagram "   .

hope this !

    best wishes to you!