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
(B) begins at 9 a.m., continuing until the supply lasts
(C) will begin at 9 a.m. and, until the supply lasts, will continue
(D) begins at 9 a.m. and, as long as the supply may last, it continues
(E) will begin at 9 a.m. and continue as long as the supply lasts


why not A?