Choice "B" is correct. A computer-based system will almost always be "more efficient" in doing something that has to be done multiple times. Thus, if multiple financial statements have to be produced, for example, at multiple times during the closing process, a computer-based system will normally be more efficient.
Choice "c" is incorrect. A computer-based system requires a set of internal controls that are just as stringent as a manual system. The controls will be different, but that does not mean they will be less stringent.
Choice "a" is incorrect. There is nothing about a computer-based system that guarantees increased accuracy. Garbage in.
Choice "d" is incorrect. There is nothing about a computer-based system that eliminates the need to reconcile control accounts and subsidiary ledgers.