Answer: Choice 2
invalid. The inner circle is plants, and the outer circle is those with cells.
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Further Explanation:
If we throw a dart at random, and we land in the inner circle (plants), then we automatically land in the outer circle (has cells).
Now imagine the dart landed in the "has cells" circle, but outside the smaller circle. This could be stuff like animal cells, bacteria, etc. So just because something has cells it does not automatically make it a plant. Saying "an iris has cells" is not enough info to be able to tell it's a plant or not. This means the conclusion of "irises are plants" is shaky at best.
This is why the overall argument structure is invalid.
For more information, check out the concept of "affirming the consequent" which is a common fallacy people make.
