Question

In what field did significant technological innovation occur in the late 1800s? *

a. building materials
b. communications
c. transportation
d. all of the above

Answer 1

Best answer would be All of the above

Answer 2

It was primarily in "all of the above" fields that significant technological innovations occurred in the late 1800s, since this was the time of the railroad, the train, and the "tall" buildings, among many other things.