When an unbalanced force acts on an object,
a. the weight of the object decreases.
b. the inertia of the object increases.
c. the object accelerates.
d. the object’s motion does not change.

You need to be more specific.  i really don't know what a "motion map" is.you can draw a graph of an object's position, distance, displacement, speed,velocity, or acceleration versus time, or you can draw a graph of the object's x-position versus its y-position and not give any information about time at all.if the graph presents position or displacement against time,  then constant velocity is a straight line . . i.e. a line that has  constant slope.if the graph shows speed against time, then constant velocityis a horizontal piece of line.if the graph shows acceleration against time, then constant  velocity is a piece of line that lies on the x-axis . . it's value is zero. 

In psychology, a person who thinks that upbringing and environment are much more important than genes is more on the side of in the nature versus nurture debate.the answer in the blank is letter b which is nature. they are more on the nature and environmental side than the genetic side of species.