Research Regarding Learning a Second Language Yields Which One of the Following

Multiple Choice

Research regarding learning a second language yields which one of the following conclusions?

A) The ability to learn a second language increases with age until adulthood, when it starts to decline.
B) The ability to learn a second language increases with age until adolescence, when it starts to decline.
C) The ability to learn a second language is greatest before age 4.
D) At this point, it appears that there is no single "best" time to learn a second language.