What was one effect of crowded tenement living? O A. Strong police patrols
B. Parks for leisure activities
C. Good schools for kids
D. The spread of disease

D

Explanation:

was quickly and deadly spread of disease. this was due almost entirely to the fact that people in these conditions were very close, meaning the disease would spread faster

explanation:

there are two statements that are incorrect.

1. the marshall plan was a lend lease program. it was an economic plan that europe redevelop itself after wwii.

2. einstein didn't really do anything to further the allied cause in building the bomb. he merely sent a letter to fdr telling him (in 1939) that if the united states entered the war, perhaps it would be wise to build the bomb before germany did. i would say this answer is incorrect, but when america entered the war 2 years later, fdr thought it might be a good idea to take einstein's advice.

the 4th choice is definitely so wrong that is likely the single answer of this question

b. germany and italy