Select the incorrect statement with respect to the category, 'genus'.

Options

A. It is a group or assemblage of related species.
B. A genus essentially possesses more than one number of species.
C. Lion, Tiger, Leopard, Jaguar are closely related species which have been placed in the genus Panthera and are respectively named as Panthera leo, P. trgris, P. pardus and P. onca.
D. Solanum, Penicillium, Withania and Canis are the examples of genera.

Explanation

To solve the question regarding the incorrect statement about the category 'genus', we can follow these steps:

### Step 1: Understand the Definition of Genus
- The genus is a principal taxonomic category that ranks above species and below family. It groups together species that are closely related.

### Step 2: Analyze Each Statement
- We need to evaluate each statement provided in the options to determine which one is incorrect.

### Step 3: Evaluate the First Statement
- **Statement 1**: "It is a group or assemblage of related species."
- This statement is correct. A genus indeed consists of related species.

### Step 4: Evaluate the Second Statement
- **Statement 2**: "A genus essentially possesses more than one number of species."
- This statement is misleading due to the word "essentially." A genus can consist of only one species (monotypic) or more than one species (polytypic). Therefore, this statement is incorrect.

### Step 5: Evaluate the Third Statement
- **Statement 3**: "Lion, tiger, leopard, jaguar are closely related species which have been placed in genus Panthera."
- This statement is correct. All these species belong to the genus Panthera.

### Step 6: Evaluate the Fourth Statement
- **Statement 4**: "Canis, Felis, and Panthera are examples of genera."
- This statement is also correct. Canis (dogs), Felis (cats), and Panthera (big cats) are all valid genera.

### Conclusion
- After evaluating all statements, we find that the incorrect statement is the second one, which claims that a genus must have more than one species.

### Final Answer
- The incorrect statement with respect to the category 'genus' is: **"A genus essentially possesses more than one number of species."**

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