Assuming a constant playback speed, which will cause the illusion ...

[mwit1967]

Assuming a constant playback speed, which will cause the illusion of
  slow motion?

 
 

a. low frame density
  b. high frame density
  c. slower primary motion
  d. slower secondary motion
  e. slower tertiary motion

Question 2

What aesthetic phenomenon will cause us to perceive slower-than-normal
  z-axis speed?

 
 

a. a minimal change in relative object size
  b. reduced distance of object travel
  c. a slow zoom-out
  d. trucking the camera slowly
  e. a rapid change in distance

[sabina576]

Answer to Question 1

b.

Answer to Question 2

a.

[mwit1967]

Excellent

[Joy Chen]

Great answer, keep it coming