The transition to adulthood has changed dramatically since
the 1950s due to individualistic culture. The "new adulthood" is the
results of a society prioritizing and emphasizing the individual's idea of adulthood over the society's "standards". The culture fosters the idea of
independence rather than identifying with a group.
For the first question, the answer is true and for the second one, the answer is C. America was the first to send a man to the moon
It promoted the (relatively) rapid diffusion of immigrants, language, and domesticated crops and animals. Those factors are examined in excellent detail in Jared Diamond's book, "Germ, Guns and Steel" which I highly recommend for anyone studying the development of world cultures. It's a long read, but well worth it.