Answer:
Option 3
Step-by-step explanation:
For Option 1;
The ratio of string instruments to percussion instruments is as shown below;
We can see that the constant of proportionality isn't 2 so this is not the correct option.
For Option 2;
The ratio of string instruments to percussion instruments is as shown below;
We can also see that the constant of proportionality isn't 2 so this is not the correct option.
For Option 3;
The ratio of string instruments to percussion instruments is as shown below;
We can see from the above that the constant of proportionality is 2 so this is the correct option