A___ should follow a dependent clause when the dependent clause comes first in a sentence

A comma should follow a dependent clause when the dependent clause comes first in a sentence. A dependent clause is the clause which cannot stand alone in its meaning on the other hand independent clause refers to the phrase which can stand alone, though both have a subject and a verb

Explanation:

she could put on music that makes her sleep

the answer should be d) he was one of those young thousands who greeted the war with a certain amount of relief, welcoming the liberation from webs of tangled emotion" since it is the best option because it shows his desire to free himself. 

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