**Most important factor in selecting a survey station is:**

1. **Distance between two stations:**
The distance between two survey stations plays a crucial role in the selection process. It is important to ensure that the distance between stations is appropriate to accurately capture the required data. If the stations are too close to each other, the measurements may suffer from errors due to limited visibility and difficulty in establishing accurate angles. On the other hand, if the stations are too far apart, it may lead to excessive time and effort to cover the survey area, making the process inefficient. Therefore, selecting an optimal distance between survey stations is essential for reliable and efficient surveying.

2. **Intervisibility:**
Intervisibility refers to the ability to establish a direct line of sight between survey stations. It is crucial to select survey stations that have clear visibility to each other in order to accurately measure angles and distances. This is particularly important for triangulation surveys, where intervisibility ensures the formation of well-conditioned triangles. Well-conditioned triangles have angles that are close to 60 degrees, resulting in accurate measurements. Therefore, the availability of intervisibility between survey stations is an important factor to consider in the selection process.

3. **Intervisibility and well-conditioned triangle:**
In addition to intervisibility, the formation of well-conditioned triangles is significant in surveying. Well-conditioned triangles have angles that are close to 60 degrees, which minimizes measurement errors and ensures accurate calculations. Therefore, selecting survey stations that form well-conditioned triangles is crucial for reliable surveying results. This factor is closely related to intervisibility, as clear visibility between stations enables the formation of well-conditioned triangles.

4. **Accessibility and distance:**
While distance is important, accessibility to survey stations is also a significant factor to consider. Surveyors need to access the selected stations easily and safely to perform their measurements. In some cases, difficult terrain or obstacles may hinder access to certain locations, making them less desirable for surveying. Therefore, selecting survey stations that are easily accessible is crucial to ensure smooth operations and minimize logistical challenges.

In conclusion, the most important factor in selecting a survey station is the interplay of intervisibility and well-conditioned triangle formation. These factors ensure accurate measurements and reliable surveying results. Additionally, the distance between stations and their accessibility are important considerations to optimize efficiency and ease of surveying operations.

Intervisibility and well conditional triangle