During the Battle of Britain, what advancement allowed the British to
hold off the German bombing of
London?
A. OSRD
B. RADAR
C. SONAR
D. USAF

B. Radar

Explanation:

Their radar early warning, which was the most advanced and the most operationally adapted system in the world, gave Fighter Command adequate notice of where and when to direct their fighting forces to repel the German bombing raids.

I hope this helps. I am sorry if you get this wrong.

b

explanation:

roosevelt believed that in light of the country's recent military successes, it was unnecessary to use force to achieve foreign policy goals, so long as the military could threaten force. this belief, and his strategy of “speaking softly and carrying a big stick,” shaped much of roosevelt's foreign policy.