Which of the following statements about the development of language over time is true?
a.
languages remain static and unchanging over time.
b.
languages can be influenced by internal forces but are rarely affected by outside cultures.
c.
most people who speak the same language have identical vocabulary and pronunciation, no matter where they live.
d.
languages are always changing and are influenced by trade, communication, and migration.

select the best answer from the choices provided.

a
b
c
d