Duchamps' were ordinary manufactured objects placed in an art context. It laid the groundwork for Conceptual art in the 1970s.

Ais the correct one.

Ihave no idea what are some of the examples

It is interweaving of the melodic lines with harmony

If the measure is suppose to have six beats and we need 1 note and 1 rest, we can either do a whole note with a half note rest after that since a whole note equals 4 beats and a half note rest equals 2 beats or we could do a whole note rest with a half note after that since a whole note rest is 4 beats and a half note is 2 beats