The event would best complete those timeline is ''1876 Colorado admitted to the Union''
Answer: Option B
Explanation:
According to the events which are given in the question above, all are related to some kind of development in the technology and sims at making human life easier and more efficient.
Following those events, then came the event of 1879 when Thomas Edison invented and made incandescent electric bulb for the first time which made electricity to the people. His purpose was to make electricity accessible to all the people in the world and not only being limited to the rich in the society.
