Answer:
B. the description of how the Temple of the Sun can be used.
Step-by-step explanation:
The detail provided in "Eyes on the Skies" that best supports the idea that the Incas used Machu Picchu as an observatory is the description of how the Temple of the Sun can be used. The Temple of the Sun is part of the archaeological complex in Machu Picchu. It was used to offer tributes, present offerings to the sun and as a place from which to measure the stars and solstices.