How Did the Requirements for Operating a Typewriter Differ from Those

How did the requirements for operating a typewriter differ from those for operating a sewing machine?

A) Sewing machine operators had to attend trade schools and were considered skilled labor, whereas typists learned their craft on the job.
B) The work of typists was much easier, but sewing machine operators had better job security and wages.
C) Most office managers preferred male typists, whereas sewing machine operators were mostly women.
D) Typists were required to have an education and a command of the English language, whereas operating sewing machines required little formal training.