Assertion: Elements belonging to the same group show similarity in chemical properties.
Reason: Elements of the same group have same number of valence electrons.

Options

A. Both A and R are true and R is correction explanation of the assertion.
B. Both A and R are true and R is not the correct explanation of the assertion
C. A is true but R is false
D. A is false but R is true

Explanation

To analyze the assertion and reason provided in the question, we can break it down into a step-by-step solution.

### Step 1: Understand the Assertion
The assertion states that "Elements belonging to the same group show similarity in chemical properties." This is true because elements in the same group of the periodic table have similar chemical behaviors.

**Hint:** Consider how the periodic table is structured and the significance of groups.

### Step 2: Understand the Reason
The reason given is that "Elements of the same group have the same number of valence electrons." This statement is also true. Elements in the same group indeed have the same number of valence electrons, which is a key factor in determining their chemical properties.

**Hint:** Reflect on what valence electrons are and their role in chemical reactions.

### Step 3: Connect the Assertion and Reason
The assertion and reason are connected because the similarity in chemical properties among elements of the same group can be attributed to their identical number of valence electrons. This means that the reason provides a valid explanation for the assertion.

**Hint:** Think about how valence electrons influence bonding and reactivity.

### Step 4: Conclusion
Since both the assertion and reason are correct, and the reason correctly explains the assertion, we can conclude that both statements are true, and the reason is the correct explanation of the assertion.

**Hint:** Consider how conclusions in logical reasoning are drawn based on the truth of the statements involved.

### Final Answer
Both the assertion and reason are correct, and the reason is the correct explanation of the assertion.