What technique did Franz Joseph Haydn use to keep his audiences guessing or on the edge of their toes?

c. the branch of philosophy that deals with beauty and how it is expressed and appreciated

that is true. stravinsky's rite of spring ballet is a prime example of with its focus on prehistoric culture, costumes, and dancing.

i believe the answer is: a.  abstract forms were often used to represent human figures.

representing human figures in abstract forms is often used in the geometric period, not hellenistic  period.   during the hellenistic  period,   aesthetic value derived from creating arts which mimic the actual shape of a certain object or individuals.

hope this ! < 3