Which of the following sentences is from a firsthand biography?

i completed my first concerto when i was fifteen.
i wanted to go to the olympics but did not make it.
i want to tell you about the greatest man who ever lived.
i joined the dance company in 1995.

I completed my first concerto when I was fifteen.

This is the best example of a firsthand biography. In this sentence, the author tells us about his own life. He talks about himself and the significance that this event had in his life. Moreover, he tells us about an important event, which is likely to have been included in a firsthand biography.

recent news about two years ago indicates that a polish forestry student by chance unearthed at a depth of about 40cm (16 inches), during digging in a damp polish forest he found a 13-page manuscript into a thermos flask.

greek jew marcel nadjari was a aischwitz slave who witnessed how the nazi's built big death chambers and crematoriums and told how he was forced to escort fellow jews to the gas chambers. he accounts on this manuscript how the nazi's disguised this chambers to look like showers. also, he describes this place as a process of extermination from the chambers to the trains arriving to take the bodies.

to convince americans of the importance of others.