A fugue subject A. Must use every note in the scale.

B. Should be instantly recognizable.

C. Can be boring and nondescript, as long as it fits in the scale.

D. Does not appear until the second episode.

In music, a fugue (/fjuːɡ/) is a contrapuntal compositional technique in two or more voices, built on a subject (a musical theme) that is introduced at the beginning in imitation (repetition at different pitches) and which recurs frequently in the course of the composition.

Explanation:

1492

columbus changes the shape of the world

ferdinand and isabella unite and create catholic spain

jews and moslems driven out of spain

lorenzo de medici dies

no one buying art and supporting city like before, his brother had been assassinated slightly before

florence to rome renaissance shift

east to west transition of church administration to the vatican