Answer:
The correct answer is option d. "Structures/characteristics among most plants are very similar".
Explanation:
There are extensive evidence to support the evolutionary relationship among all plant taxa, however, similarity of structures and characteristics among most plants is not one of them. Plants are one of the most diverse kingdoms having very different species such as flowering plants, conifers, lichens, cycads, algae, among others. The structures and characteristics of these plants are very different among them, and this diversity makes difficult to classify and clarify the evolutionary relationship that they share.