You observe the lower limb of the Sun at a sextant altitude (hs) of 50°26.9' on 9 November. The index error is 1.5' on the arc. The height of eye is 56 feet (17 meters). What is the observed altitude (Ho)?

Correct Answer: Option C — 50°33.5'

Apply the index error (on the arc is subtractive) to the sextant altitude. Adjust for dip using the 56-foot height of eye and apply the Sun's altitude correction from the Nautical Almanac. The resulting Ho of 50°33.5' follows the rigorous correction sequence required for accurate celestial position fixing.