In working out a local apparent noon sight for your latitude, you subtract the Ho from 90°. The 90° represents the angular distance from __________.

Correct Answer: Option A — your horizon to your zenith

Per Bowditch, the zenith distance is the angular distance between a celestial body's position and the observer's zenith, measured along the vertical circle. Subtracting observed altitude (Ho) from 90° gives the arc from the horizon to the zenith.