Assertion : If magnification of real object is -2. Then, it is definitely a concave mirror.
Reason : Only concave mirror can make real images of real objects.

Options

A. (a) If both Assertion and Reason are true and the Reason is correct explanation of the Assertion.
B. (b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
C. (c) If Assertion is true, but the Reason is false.
D. (d) If Assertion is false but the Reason is true.

Explanation

To solve the problem, we need to analyze the assertion and the reason provided in the question step by step.

### Step 1: Understanding Magnification
The magnification (m) of a mirror is defined as the ratio of the height of the image (h2) to the height of the object (h1). Mathematically, it can be expressed as:
\[ m = \frac{h2}{h1} \]

### Step 2: Given Information
From the question, we know:
- The magnification (m) is -2.
- The object is real, which means the object distance (u) is positive (u > 0).
- The height of the object (h1) is positive (h1 > 0).

### Step 3: Analyzing the Magnification
Since the magnification is given as -2:
\[ -2 = \frac{h2}{h1} \]
This implies:
\[ h2 = -2 \cdot h1 \]
Since h1 is positive, h2 must be negative. This indicates that the image is inverted.

### Step 4: Identifying the Type of Mirror
In optics, a concave mirror can produce real and inverted images when the object is placed in front of it. The negative height of the image (h2 < 0) confirms that the image is inverted, which is characteristic of a real image formed by a concave mirror.

### Step 5: Evaluating the Assertion and Reason
- **Assertion**: If the magnification of a real object is -2, then it is definitely a concave mirror. This is true because the negative magnification indicates an inverted image, which is formed by a concave mirror.
- **Reason**: Only a concave mirror can make real images of real objects. This is also true, as concave mirrors are the only type of mirror that can produce real images for real objects.

### Conclusion
Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the final answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

---