Consider the following four statement A, B, C and D and select the right option for two correct statements :-
(A) Dominance is not an autonomous feature of a gene
(B) In case of co-dominance of `F_(1)` geneartion resembled either of two parents
(C) Due to dominance alleles do not show any blending
(D) In ABO blood type four types of phenotypes are formed
The correct statement are

Options

A. A and B
B. B and C
C. C and D
D. A and D

Answer

To solve the question, we need to analyze each of the four statements (A, B, C, and D) and determine which two are correct.

### Step-by-Step Solution:

1. **Evaluate Statement A**:
- **Statement**: Dominance is not an autonomous feature of a gene.
- **Analysis**: This statement is correct. Dominance is a relationship between alleles, not a characteristic of the gene itself. It depends on the interaction between alleles in a heterozygous condition.

2. **Evaluate Statement B**:
- **Statement**: In case of co-dominance, the F1 generation resembled either of the two parents.
- **Analysis**: This statement is incorrect. In co-dominance, the F1 generation exhibits traits from both parents simultaneously, rather than resembling just one parent.

3. **Evaluate Statement C**:
- **Statement**: Due to dominance, alleles do not show any blending.
- **Analysis**: This statement is misleading. The lack of blending is due to the independent segregation of alleles rather than dominance itself. Therefore, this statement is incorrect.

4. **Evaluate Statement D**:
- **Statement**: In ABO blood type, four types of phenotypes are formed.
- **Analysis**: This statement is correct. The four phenotypes are A, B, AB, and O, which are indeed the result of the ABO blood group system.

### Conclusion:
Based on the evaluations:
- **Correct Statements**: A and D are correct.
- **Incorrect Statements**: B and C are incorrect.

### Final Answer:
The correct statements are A and D.

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