What has been the most important cause of productivity growth in the U. S. labor force?
A) progress in medicine
B) progress in technology
C) progress in communication
D) progress in labor laws and regulations

What explains the increase in life expectancy in botswana? a. the increased availability of jobs and an improved economy b. access to antiretroviral drugs, hiv/aids education, and widespread hiv/aids testing c. a series of military takeovers that stabilized the political system and led to education reform and increased literacy rates d. a recent military coup that led to an improved healthcare system select the best answer from the choices provided.