The invention of the telegraph
a. let distant locations communicate quickly.
b. kept distant locations from communicating quickly.
c. was 50 years after the railroad.
d. was 50 years before the railroad.

Let distant locations communicate quickly.

Explanation:

The Telegraph is a communication system that was created in the eighteenth century, widely used by industries and governments, with the aim of transmitting messages from one point to another, over great distances.

Telegraphs used codes to reliably and quickly transmit information. The main code used by the telegraphs was the Morse code, which came with the creation of an electric telegraph in the 1830s. The telegraph fell out of use after the telephone was created.

its b they wanted to be able to expand their trade..