Assertion :- Mendel proposed that in a true breeding, tall or dwarf pea variety the allelic pair of genes for height are identical i.e. TT and tt respectively.
Reason :- Alleles can be similar as in the case of homozygotes or can be dissimilar as in the case of heterozygotes.

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are trur but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is Flase.
D. If both Assertion & Reason are false.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that Mendel proposed that in true breeding tall (TT) or dwarf (tt) pea varieties, the allelic pairs for height are identical. This means that for a tall pea plant, the genotype is homozygous dominant (TT), and for a dwarf pea plant, the genotype is homozygous recessive (tt).

2. **Evaluating the Assertion**: The assertion is true. Mendel's experiments with pea plants showed that true breeding varieties have identical alleles for a trait. Therefore, the statement that TT represents tall plants and tt represents dwarf plants is correct.

3. **Understanding the Reason**: The reason states that alleles can be similar (homozygous) or dissimilar (heterozygous). This means that in a homozygous condition, both alleles are the same (like TT or tt), while in a heterozygous condition, the alleles are different (like Tt).

4. **Evaluating the Reason**: The reason is also true. It accurately describes the nature of alleles in genetics, distinguishing between homozygous and heterozygous conditions.

5. **Determining the Relationship**: Although both the assertion and reason are true, the reason does not directly explain the assertion. The assertion specifically addresses the nature of true breeding varieties, while the reason discusses the general concept of alleles.

6. **Conclusion**: Since both the assertion and reason are true but the reason does not explain the assertion, the correct answer is that both assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, but the reason is not the correct explanation of the assertion.

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