Answer:

The correct answer is option 'B' - Cross-staff survey.

Explanation:

A cross-staff survey is a type of surveying technique used to locate boundaries of a field and determine its area. It involves the use of a cross-staff, which is a simple surveying instrument consisting of a wooden staff with perpendicular arms. The cross-staff is used to measure angles and distances in the field.

Process of a Cross-staff Survey:
1. Setting up the cross-staff: The surveyor sets up the cross-staff at a known point on one side of the field and makes it level by adjusting the vertical staff.
2. Taking angular measurements: The surveyor aligns the cross-staff with two reference points, such as two trees or landmarks, on opposite sides of the field. The angles between the reference points and the cross-staff are measured.
3. Recording measurements: The surveyor records the measured angles and the distance between the cross-staff and each reference point.
4. Calculating the area: Using trigonometry and mathematical calculations, the surveyor can determine the area of the field based on the recorded measurements.

Advantages of Cross-staff Survey:
1. Simple and inexpensive: The cross-staff survey requires minimal equipment and is cost-effective compared to other surveying techniques.
2. Quick and efficient: The survey can be carried out relatively quickly, making it suitable for smaller fields or areas.
3. Accurate for regular-shaped fields: The cross-staff survey is accurate for fields with regular shapes, such as rectangular or square fields.

Limitations of Cross-staff Survey:
1. Not suitable for irregular-shaped fields: The cross-staff survey may not provide accurate results for fields with irregular shapes, as it assumes a regular boundary.
2. Limited precision: The accuracy of the cross-staff survey depends on the skill of the surveyor and the instrument used. It may not be as precise as more advanced surveying techniques.
3. Relies on visual alignment: The surveyor needs to visually align the cross-staff with the reference points, which may introduce human error.

In conclusion, a cross-staff survey is a surveying technique used to locate field boundaries and determine their areas. It is a simple and cost-effective method, suitable for smaller fields with regular shapes. However, it may not be as accurate or precise as more advanced surveying techniques.