The father as well as (a)/ the sons were (b)/mysteriously missing(c)/from the house (d)/No error (e) | Sentense error/Grammatical error

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Sentense error/Grammatical error
The father as well as (a)/ the sons were (b)/mysteriously missing(c)/from the house (d)/No error (e)
1.(a)
2.(b)
3.(c)
4.(d)
5.(e)
Correct Answer: b [“was” should be used in place of “were”]