Which ONE of the following CORRECTLY matches the metrology instruments and their respective most common applications?
| Metrology Instrument | | Application | |
|---|
| P | Sine bar | 1 | Surface roughness of milled planar surface |
| Q | Profilometer | 2 | Planar surface inclination of a part |
| R | Vernier calliper | 3 | Checking shaft diameter tolerance without direct measurement |
| S | Ring GO gauge | 4 | Length of any side of a cuboid |