Incorrect about innate immunity is :-

Options

A. present before any exposure a pathogen
B. effective from the time of birth
C. only in vertebrates
D. largely non-specific

Answer

To determine which statement about innate immunity is incorrect, let's analyze each option provided:

1. **Present before an exposure to a pathogen**: This statement is correct. Innate immunity is indeed present from birth and does not require prior exposure to a pathogen to be effective.

2. **Effective from the time of birth**: This statement is also correct. Innate immunity is functional at birth and provides immediate defense against pathogens.

3. **Only in vertebrates**: This statement is incorrect. Innate immunity is not exclusive to vertebrates; it is also present in invertebrates. Organisms like insects and mollusks have innate immune mechanisms.

4. **Largely non-specific**: This statement is correct. Innate immunity is characterized by its non-specific nature, meaning it responds to a wide range of pathogens without targeting specific ones.

Based on this analysis, the incorrect statement about innate immunity is **"only in vertebrates."**

### Step-by-Step Solution:
1. **Identify the characteristics of innate immunity**: Understand that innate immunity is a type of defense that is present at birth and does not require prior exposure to pathogens.

2. **Evaluate each option**: Go through each statement one by one to determine its accuracy regarding innate immunity.

3. **Determine the incorrect statement**: After evaluating the options, identify which statement does not accurately describe innate immunity.

4. **Conclude with the answer**: The statement that is incorrect about innate immunity is "only in vertebrates."