803. The use of the bar code, or Universal Product Code, which was created in part to enable supermarkets to process customers at a faster rate, has expanded beyond supermarkets to other retail outlets and have become readily accepted despite some initial opposition when it was first introduced in 1974.
Meaning:The use of the bar code, or Universal Product Code we are talking about use of bar code/UPC
which was created in part to enable supermarkets to process customers at a faster rate Which = UPC or bar code
Was = verb = singular for singular subject bar code
Subject -verb pair present in the which/prepositional clause
has expanded beyond supermarkets to other retail outlets Has expanded = singular present perfect verb for singular subject “ The use”. Present perfect as bar code was developed in past but the use of it still valid in present
and have become readily accepted despite some initial opposition And = connector
So subject “the use” has two verb
1. Has expanded
2. have become = plural= incorrect. We need singular verb for this
when it was first introduced in 1974. “when” a time marker to show opposition was there when it was launched initially.
“it” = singular bar code
(A) have become readily accepted despite some initial opposition when it was first introduced in 1974
SV pair doesn’t match.
(B) has become readily accepted despite some initial opposition when they were first introduced in 1974
“they” is incorrect. Need singular “it” for singular “the bar code”
(C) have become readily accepted despite some initial opposition when first introduced in 1974
SV pair doesn’t match
(D) has become readily accepted despite some initial opposition when the bar code was first introduced in 1974
Correct
(E) bar codes have become readily accepted despite some initial opposition when it was first introduced in 1974