This will be subject to much in way of interpretation and analysis.  I think that individuals could be used to justify each and it is up to the historical opinion to find examples to meet each criteria.  I would say that it is a challenge to find individuals who are born great, this often refers to monarchs and nobles who have greatness attached to them from birth.  From another perspective, in my mind, I would think that someone like Abraham Lincoln is someone who was "born great."  Lincoln was born in the proverbial "one room log cabin."   He represented the ultimate in modesty and in humility.  Lincoln learned to cope without much in way of economic wealth and prosperity, understood the dangers of not possessing an education, and was mostly driven by his own sense of identity and desire to better himself.  This narrative of birth is what enabled Lincoln to be "born great."  In terms of individuals who achieved greatness, I would point to innovators in the field of medical science.  Individuals like Jonas Salk would be an example of an individual who achieved greatness through tireless endeavor and labor, driven by a singular goal and purpose.  Through his work, Salk was able to achieve greatness as his name is synonymous with an individual who was able to attain a greatness from which many benefit.  Finding someone who had greatness thrust upon them would be someone like Dr. Martin Luther King, Jr.  In my mind, Dr. King represents the idea of someone who had greatness thrust upon them because he was not looking to be the face of the Civil Rights Movement.  Responding to the call in what Dr. King would call "the fierce urgency of now," Dr. King understood that he would be needed as the face of the Civil Rights Movement.  It was a monumental task that few, if anyone else, could represent.  Yet, Dr. King understood that his greatness was contingent on his ability to seize the moment and make it both his own and a moment for millions of others.  For this reason, I would consider him someone who met the call of greatness being thrust upon him.