Guido d'Arezzo contributed to the development of: A. time signatures.
B. musical notation.
C. musical instruments.
D. direct psalmody.

The answer is B. (Musical notation)

Match these items. match the items in the left column to the items in the right column. 1. aesthetics in art, a technique for defining shape, also used to create a sense of depth 2. composition a perceived line that describes three-dimensional form 3. contour line a method of presenting an illusion of the three-dimensional world on a two-dimensional surface 4. line (pronounced "uhvrr") — a work of art; the sum of the lifework of an artist, writer, or composer 5. oeuvre the way an artist organizes forms (lines, shapes, etc.) in an artwork, either by placing shapes on a flat surface or by arranging forms in space 6. patron the relationship of one part of a person, building, or object to another; for example the size of a statue's head in relationship to the rest of the body 7. personification the study of beauty or good taste; anything related to the study of beauty or good taste 8. perspective giving human characteristics to something that is not human 9. proportion generally a wealthy person who pays an artist to create a work of art; throughout much of history artists could not have survived without "patronage" 10. symbol an object or word or gesture that represents something else