The reason why the system of plant classification proposed by Carolus Linnaeus was artificial is

The correct option is: Because it was based on the similarities and differences in floral and other morphological characters only

Step-by-Step Explanation:

1. Understanding Carolus Linnaeus's System:
Carolus Linnaeus introduced a system of plant classification in the 18th century. His classification system is widely known as an artificial system of classification because it relied on a very limited number of observable physical features (morphological characters) to group plants, rather than their evolutionary histories or internal physiological details.

2. Why it is called "Artificial":
An artificial system uses arbitrary, easily observable external traits—such as the number and arrangement of stamens and carpels in flowers, size, shape, and color of leaves—to classify organisms. In Linnaeus's sexual system of classification, plants were grouped primarily based on floral characters (specifically the number and characteristics of stamens and styles).

3. Limitations of the Artificial System:
Because this system only considered a few superficial similarities and differences in floral and vegetative morphology, it often grouped completely unrelated plants together and separated closely related ones. It did not take into account anatomical, embryological, physiological, or evolutionary (phylogenetic) relationships, which are the foundations of modern natural and phylogenetic classification systems.

4. Conclusion:
Therefore, the system is artificial precisely because it was based on the similarities and differences in floral and other morphological characters only, ignoring deeper genetic and evolutionary connections.