D.
it's D because it's coming from a person that was there. A primary source comes from a person involved, saw it or was there
They are a positive demonstration of how to treat your elders w respect. The unproven yet popularly believed invention of karate was a very positive social influence, as it not only teaches a sport, but manners, etiquette, self esteem, respect for others, & many more qualities I feel are important socially. They have produced many great musicians who have contributed to classical music.
Answer:
He believed Gemini spacecraft could fly in lunar operations before Project Apollo, and cost less. NASA's administration did not approve those plans.
