(A): Transition elements form alloys very easily.
(R): They exhibit variable oxidation states.

Options

A. Both A & R are true, R is the correct explanation of A
B. Both A & R are true, R is not correct explanation of A
C. A is true, R is false
D. A is false, R is true

Answer

To solve the assertion and reason question, we need to analyze both statements carefully.

### Step 1: Understand the Assertion
The assertion states that "Transition elements form alloys very easily."
- **Explanation**: Transition metals are known for their ability to form alloys due to their similar atomic sizes and metallic bonding characteristics. Alloys are solid solutions of metals or a metal with non-metals, and transition metals can easily occupy each other's lattice positions because of their comparable atomic radii.

### Step 2: Understand the Reason
The reason states that "They exhibit variable oxidation states."
- **Explanation**: Transition metals are characterized by their ability to exhibit multiple oxidation states due to the involvement of their d-electrons in bonding. This property is a result of their electronic configuration, which allows them to lose different numbers of electrons.

### Step 3: Analyze the Relationship
Now, we need to determine if the reason provided explains the assertion.
- While it is true that transition metals exhibit variable oxidation states, this property does not directly relate to their ability to form alloys. The formation of alloys is primarily due to their similar atomic sizes and the ability to occupy each other's lattice sites, rather than their oxidation states.

### Conclusion
Both the assertion and reason are correct statements, but the reason does not correctly explain the assertion. Therefore, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion.

### Final Answer
- **Assertion (A)**: True
- **Reason (R)**: True
- **Conclusion**: The reason is not the correct explanation for the assertion.