The correct answer is letter A: Faith.
Martin Luther King Jr. believed that salvation and approval from God was only found by people who had Faith, and also applied God's principles throughout their whole lives.
The King Family also wrote 10 life lessons they believed would help people to have a spiritual and moral conduct through life that said: make home a priority, serve your family, get good education, guard your heart, defend life, fight for justice, care for the needy, work for peace, build the beloved community and find your joy.