“speak softly and carry a big stick.”

this quote explains the idea behind theodore roosevelt’s big stick diplomacy. in practice, what does it mean?

a. the united states should pull all military presence out of foreign countries.
b. the united states should invest a lot of money to develop the infrastructure of poor countries.
c. the united states should sometimes use the threat of force to persuade a foreign country.
d. the united states should conquer as many neighboring countries as possible.