1. Condition for minimum deviation in a prism

For a prism, the deviation is minimum when the path of light through the prism is symmetric. This gives the standard condition:

$i=e$

where:

• $i$ = angle of incidence
• $e$ = angle of emergence

Also, at minimum deviation,

$r_1=r_2=\frac{A}{2}$

where $A$ is the prism angle.

2. Check statement (A)

Incident ray and emergent ray are symmetric to the prism.

At minimum deviation, the light path is symmetric inside the prism, and the incident and emergent rays are symmetric with respect to the prism.

So, (A) is true.

3. Check statement (C)

Angle of incidence is equal to that of the angle of emergence.

This is the direct condition for minimum deviation:

$i=e$

So, (C) is true.

4. Check statement (B)

The refracted ray inside the prism becomes parallel to its base.

At minimum deviation, the refracted ray inside the prism is parallel to the base of the prism (for the usual prism geometry). This is a standard geometrical result.

So, (B) is true.

5. Check statement (D)

When angle of emergence is double the angle of incidence.

There is no such condition for minimum deviation. In fact, at minimum deviation,

$e=i$

not $e=2i$.

So, (D) is false.

6. Choose the correct option

True statements: (A), (B), and (C)

Hence the correct option is:

$\boxed{\text{C}}$

7. Comparison with stored answer

Stored correct answer = C

My derived answer = C

So, they agree.