Geneticist: Ethicists have fears, many of them reasonable, about the prospect of cloning human beings, that is, producing exact genetic duplicates.
Conclusion
The idea that a wealthy person will create an army of exact duplicates is completely unrealistic.
Evidence
Clones have to be raised and educated, which is a long-term process that would never produce identical adults when it comes to the original in terms of outlook, personality, or goals.
Evaluate
When we read Role or Main Conclusion, we read the paragraph expecting that the Conclusion will appear earlier than the Support. Specifically, it will usually be the very first claim or it will be some but / yet / however rebuttal.
Here, we start with an attribution to something that ethicists believe, and then we get a But pivot into our author's conclusion.
The last sentence could debatably be considered 2nd premise, but it's more of an add-on thought. It's not really support for the author's conclusion. The author's conclusion is only trying to convince us that "an army of exact duplicates is unrealistic", so we only care to hear why that is not realistic, not about what other stuff is more realistic.
Goal
They're asking us about the 3rd sentence, which is the premise for our author's conclusion.
So let's look for, .