"Well I'm already here. What do you need me to do?"
"For now just disrobe and wait here. We'll bring everything necessary in a few moments." said the doctor, leaving with your clothes. You sit on one of the sofas, being careful to cover your junk. There's a TV in the room and idly start surfing for something to watch.
Suddenly another door opens, and out step someone. You are a bit surprised to see another naked person come out of it. Perhaps the experiment was to be done in group. You suddenly feel a bit more naked now, but the doctor comes after the new person and calls you over.
"What do you think of him? It is our greatest achievement."
"Uh?" You seem confused and look at the lanky youth, he seems to be about your age, perhaps a bit more underdeveloped, but nothing else remarkable about him, until suddenly you see his face, something odd something...
"It is quite remarkable isn't it? It is not a complete match but that's nurture for you."
"Wait... you mean?" The doctor see you with a smile and nodding, corroborating your fears. He looked like you, if you hadn't had a haircut in months or been outside in the sun. "But how?"
"Remember the sample that you gave us? We used it on our human cloning experiments, this young lad here, C-1 is the result. We modified him to rapidly age until he matched your age, but he doesn't have the cognitive function of a full fledge 17 year old. He should mentally be around 2 or 3. And as I can visually estimate the artificial puberty was also off." He said while looking at your junk that was a good 5'' with a healthy patch of hair versus C-1's 3'' and a few wisps. "But that's why we brought you here to perfect the process as much as possible. Oh, by the way, I know we already talked about this but since this experiments are highly classified we'll have to give you a codename too, to protect your identity, from now on you shall be referred as C-0, is that ok?"
"Dude, I'm not even over the fact that you cloned me!"
"C-1 is just the first, during this week we also managed to create C-2 and C-3, would you like to meet them?" He turned to speak to a piece. "Send C-2 and C-3"
From the same door than before came two other persons all naked. All you. The second one was a bit bigger than you, not just taller but he also had more defined muscles and was more hairier than you, with thick pit hairs and chest hair that merged into the happy trail into a forest of pubes that continue all along the legs, and a snake that actually escaped from such foliage. The third on the other hand was a boy, but this time C-0 had no trouble recognizing him, he looked like the splitting image of you when you were a boy.
"C-2 here was under a more heavy dose of Artificial Puberty, as you can see the result is pretty obvious, you can argue that it is an improvement perhaps. C-3 on the other hand is under a slower maturing process, we hope that this will allow puberty to set on "naturally""
"I- I am speechless."
"Well now back to the reason you are here. Now that we have this points of reference we need data to determinate how to get to the target that it is you. This whole room is able to monitor you four, ergo our insistence on the nudity. You simply have to interact with them. That is all."