Options A, B, and C shows that quadrilateral LMNP on the coordinate plane is a parallelogram
Analysis of the options
A. Show that the midpoint of LN is the same as the midpoint of MP*
This condition is true for parallelograms, as opposite sides of a parallelogram have the same midpoint.
B. Show that LN = MP
This condition is true for parallelograms. Opposite sides of a parallelogram are equal in length.
C. Show that LM = NP and MN=LP
This condition is true for parallelograms. Opposite sides of a parallelogram are equal in length.
D. Show that slope of overline LN slope of overline MP = -1
This condition is not generally true for parallelograms. The slopes of opposite sides of a parallelogram are negative reciprocals of each other, not necessarily -1.