Concept:Use Venn diagram or set logic to deduce relationships from given statements.
Explanation:Statement 1: All plants are trees. So the set of plants is a subset of trees.
Statement 2: No tree is green. So trees and green sets are disjoint.
Therefore, plants are also disjoint from green; no plant is green.
Conclusion I: "Some plants are green" — false.
Conclusion II: "Those plants which are not trees are green."
Since all plants are trees, there are no plants that are not trees. The statement refers to an empty set, so it cannot be concluded as valid in syllogism (existential fallacy). Hence, it does not follow.
Thus neither conclusion follows.
Answer:Option D: if neither I nor II follows.