I am so sorry you've had to wait so long. I've kind of gone AWOL for the entire summer, and the number of hours this question has gone overdue is one of the results from that...
(A) The highest altitude a human can survive in, referred to as the death zone, is 8,000 meters, or 26,246 feet above sea level. However, for parachuting, you would be passing through this zone pretty quickly, and so could survive a jump from higher up. In fact, someone has actually jumped without supplementary oxygen from around 42,000 feet, so considerably above the death zone. Depending on how long you can hold your breath, you could parachute from a bit higher than 42,000 feet.
(B) In the same article that references the highest jump without supplementary oxygen, it mentions the highest jump ever made: 135,890 feet (which you can read more about here). If the guy who made this jump had not been wearing a special pressurized suit, apparently his blood would have boiled. In fact, it turns out that human bodily fluids begin to boil at an altitude of 63,000 feet above sea level. So 63,000 feet is probably around the upper limit without a special pressurized suit.
(C) According to this Quora answer, it depends on your velocity and mass; mostly likely you could go to the very edge of Earth's atmosphere.