What principle is involved in the tests for the halide ions in the presence of one another?

silver nitrate test

Explanation:

The silver nitrate test is helps to detect fairly small concentrations of halide ions. The mixture is acidified by adding dilute nitric acid. This prevents unreacted hydroxide ions reacting with the silver ions. Then silver nitrate solution is added and silver halide is precipitated. A white precipitate forms from silver chlorine, cream from silver bromide and pale yellow for silver iodide.

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be