In your opinion, which new piece of technology was the most important during wwi?

all of the following apply except for (a. excessive credit on real estate resulting in defaulted loans.

in 1819, panic swept the country due,in part, to the rapid expansion of american manufacturing during the war of 1812 and the distress caused by the post-war british competition. the rapid expansion of american farming was another factor.

explanation:

c or d both can be the answer