Hi Frankie! You have to actually tell us your question, this doesn't give us much information about what you need! and I also I believe this is under math, not history!
The best answer is:
Samuel Morse and the telegraph
Robert Fulton and the steamboat
<span>Cyrus McCormick (Inventor of the Mechanical Reaper) so its improved because he invented a better one than ones already invented
</span>hope this helped :)
To my knowledge, the correct answer among all of the given choices is C.) Steam. If I'm not mistaken, this was the time that more trains came into use.
I hope this is the answer you were looking for and that it helps!! :)
B). Is the right answer from my opinion.
Or federalist or anti federalist
