This propaganda poster is from World War I.

A man in work clothes and a bowler hat is shown holding a riveting gun. Behind him is a silhouette of a soldier holding a rifle. The American flag is waving in the background. The poster reads, "Rivets are bayonets. Drive them home!"

How does the poster illustrate that civilians are crucial to the total war effort?

It shows that civilians always think about the dangers soldiers face.
It parallels the work done by civilians with the efforts of soldiers.
It shows that civilians’ work helps make soldiers’ lives brighter.
It equates civilian suffering with soldiers’ suffering on the battlefield.