The sale of government surplus machinery will begin at 9 a.m. and continue until the supply lasts
(A) will begin at 9 a.m. and continue until the supply lasts [Correct]
(B) begins at 9 a.m., continuing until the supply lasts ['continuing' is wrong]
(C) will begin at 9 a.m. and, until the supply lasts, will continue [Awkward]
(D) begins at 9 a.m. and, as long as the supply may last, it continues [I think 'it' is not a clear reference]
(E) will begin at 9 a.m. and continue as long as the supply lasts [I am not sure whether it is wrong or not. Structure of sentence seems ok to me.
However I would prefer A over E]
So IMO A is the correct option.
Hey Vivek, Is there any trap?