On 13 November 1981 you observe a back sight of the lower limb of the Sun as seen through the sextant's scope. The sextant altitude (hs) is 109°26.3'. The height of eye is 66 feet, and the index error is 2.0' on the arc. What is the observed altitude (HO)?

A
70°56.6'
B
70°38.0'
C
70°27.2'
D
70°23.2'
E