Step 1: Analyzing Zircon.
Zircon is a mineral that exhibits very high positive relief in thin section, meaning it appears as a prominent, highly birefringent mineral under polarized light. It does not show pleochroism like some other minerals. Therefore, zircon corresponds to option (ii).
Step 2: Analyzing Orthopyroxene.
Orthopyroxene exhibits pink to green pleochroism, meaning the color of the mineral changes depending on the crystallographic orientation of the light passing through it. Hence, it matches option (i).
Step 3: Analyzing Muscovite.
Muscovite is characterized by cyclic twinning, which is visible in thin section under polarized light. This is a distinctive feature of muscovite and matches option (iii).
Step 4: Analyzing Cordierite.
Cordierite exhibits third order birefringence, which is a characteristic feature seen in minerals with a moderate to high birefringence. This matches option (iv).
Step 5: Conclusion.
The correct matches are as follows:
- Zircon matches with (ii) Very high positive relief
- Orthopyroxene matches with (i) Pink to green pleochroism
- Muscovite matches with (iii) Cyclic twinning
- Cordierite matches with (iv) Third order birefringence
Therefore, the correct answer is (A).
\[
\boxed{\text{P-ii; Q-i; R-iii; S-iv}}
\]
