Assertion (A) Analysis
Assertion (A) states that Whole Circle Bearing (WCB) is preferred over Quadrantal Bearing (QB).
- Whole Circle Bearing (WCB): Measures the angle clockwise from the North direction. The values range from $0^\circ$ to $360^\circ$. This system provides a unique value for every direction.
- Quadrantal Bearing (QB): Measures the angle from the North or South direction towards the East or West. It is represented as, for example, N $30^\circ$ E or S $60^\circ$ W. This system requires the reference meridian (N or S), the angle value (between $0^\circ$ and $90^\circ$), and the quadrant (E or W) for complete specification.
- Preference for WCB: WCB is generally preferred in modern surveying because it is unambiguous and simplifies calculations, especially those involving the addition or subtraction of bearings, as all angles are measured from the same reference (North). QB can be more cumbersome for complex calculations.
Therefore, Assertion (A) is correct.
Reason (R) Analysis
Reason (R) states that Bearing is completely specified by an angle.
- For Whole Circle Bearing (WCB), the bearing is indeed specified by a single angle measured clockwise from North ($0^\circ$ to $360^\circ$).
- However, for Quadrantal Bearing (QB), the specification involves more than just an angle. It requires the reference meridian (North or South), the acute angle relative to that meridian ( $0^\circ$ to $90^\circ$ ), and the quadrant (East or West). For example, N $45^\circ$ E is distinct from S $45^\circ$ E.
- Since the statement in Reason (R) is presented as a general rule for "Bearing" and it does not hold true for Quadrantal Bearings, the statement itself is not correct.
Therefore, Reason (R) is not correct.
Conclusion
Based on the analysis, Assertion (A) is correct, but Reason (R) is not correct. This corresponds to Option 5, which is presented as Option C in the provided answer.
(A) is correct but (R) is not correct.