Disadvantage of common or vernacular names is

Options

A. They are brief
B. Natives are familier with them
C. They are easier to pronounce
D. All organisms have no common names

Answer

### Step-by-Step Solution:

1. **Understanding Common Names**: Common names, also known as vernacular or trivial names, are the names used for organisms in local languages. They are not standardized and can vary from one region to another.

2. **Lack of Universality**: One of the main disadvantages of common names is that they are not universally accepted. The same organism may have different common names in different regions or languages, leading to inconsistency.

3. **Confusion in Identification**: Because common names can vary widely, they can create confusion when trying to identify or communicate about a specific organism. For example, a single species may be referred to by multiple names, which can lead to misunderstandings.

4. **Not All Organisms Have Common Names**: Another significant disadvantage is that not all living organisms have common names. Some species, especially less known or newly discovered ones, may only be identified by their scientific names.

5. **Conclusion**: Therefore, the disadvantages of common names include their lack of universality, potential for confusion, and the fact that not all organisms have common names. This makes scientific names, which are standardized and universally accepted, more reliable for identification.

### Final Answer:
The disadvantage of common or vernacular names is that they are not universally similar, can create confusion due to language differences, and not all organisms have common names.

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