The Industries That Grew Up Around the Revolutionary Inventions of Alexander

The industries that grew up around the revolutionary inventions of Alexander Graham Bell and Thomas Alva Edison demonstrated that

A) technological know-how was vital for controlling large corporations.
B) the federal government had a tight rein on industrial development at the time.
C) large corporations were particularly committed to helping people in their everyday lives.
D) the age of the inventor was becoming the age of the corporation.