Rockwell (had been attending) the new york school of art when he dropped out and enrolled at the national academy of design.
what is the tense of the verb in parenthesis?
a. simple past
b. past perfect
c. past progressive
d. past perfect progressive

Read the sentence from the war of the worlds. i turned, and as i did so the screw must have come out, for the lid of the cylinder fell upon the gravel with a ringing concussion. which option is the accurate synonym of the word concussion as it is used in the sentence? explosion disruption crash interruption