The correct answer is option 'A' - one or two-character.

Explanation:
Artificial systems of classification are methods used to classify plants and other organisms based on specific characteristics or traits. These systems are devised by humans and are not based on natural evolutionary relationships. They are primarily used for convenience and practical purposes in fields such as agriculture, horticulture, and taxonomy.

One common approach used in artificial systems of classification is to classify plants based on one or two characters. This means that plants are grouped together based on the presence or absence of a specific characteristic or trait. For example, plants may be classified based on the type of leaf arrangement (e.g., alternate, opposite, whorled) or the type of inflorescence (e.g., raceme, panicle, umbel).

Using one or two characters for classification allows for a simplified and easy-to-use system. It reduces the complexity of classification and makes it more manageable, especially when dealing with a large number of plant species. It also allows for quick identification and categorization of plants based on readily observable features.

However, it is important to note that artificial systems of classification based on one or two characters have limitations. They do not take into account the overall evolutionary relationships or genetic similarities between different plant species. Therefore, they may not accurately reflect the true relationships between plants.

In contrast, phylogenetic character-based classification and complete morphological character-based classification consider a wider range of characteristics and traits to determine the evolutionary relationships between organisms. Phylogenetic characters are features that are inherited from a common ancestor, and their presence or absence can be used to determine the relatedness between species. Complete morphological characters involve considering all possible characteristics and traits to classify organisms.

In conclusion, while artificial systems of classification based on one or two characters are useful for practical purposes, they do not provide a comprehensive understanding of the evolutionary relationships between plants. A more accurate classification can be achieved by considering phylogenetic characters or complete morphological characters.