Which of the following is primary source? a. a texas history textbook b. a documentary film about the trail of tears c. a biography of alexander graham bell published in 1995 d. a love letter written to john adams from abigail adams

D. a love letter written to John Adams from abigail adams

This is because the letter was written by the direct people and isn't second hand information.

explanation:

xbxnxbdndndn

darwinism is survival of the fittest there for social darwinism is the survival of the wealthiest