Answer:
Change
Step-by-step explanation:
Here there are two variables a and b.
a is causing variable b.
In other words, a is an independent variable which can take any values, and b takes values depending on the value of a.
Examples are: b=ma+k or b =2a^2 etc.
Whenever we change a there is a change in b.
But it should be noted when there is a change in b, there is a change in a also.
However, normally a is changed first and b is derived from a.
Hence the statement
In order to show that variable a causes variable b, you need to change_____ variable
a.
