A group of scientists want to create a new insulating material to be placed between two panes of glass in the windows of office buildings to block out sounds from the busy streets. Medium

Average Density (g/cm3)

Speed of Sound (m/s)

Paraffin Wax

0.90

1,300

Rubber

0.95

1,550

Nylon

1.15

2,600

Plexiglass

1.18

2,730

Plastic

1.2

2,080

Pyrex glass

2.32

4,960

Glass

2.6

5,170

Which medium should the scientists use to create this insulating material?
A
The scientists should use plastic because it is a soft solid and the difference in firmness will cause the speed of the sound waves to increase.
B
The scientists should use paraffin wax because as the waves pass through the paraffin wax, the difference in density will cause the sound waves to slow down.

C
The scientists should use plexiglass because as the waves pass through the plexiglass, the difference in opacity will cause the speed of the sound waves to decrease.
D
The scientists should use nylon because as the waves pass through the nylon, the difference in the chemical composition will cause the speed of the sound waves to increase.