In order to show that variable a causes variable b, you need to variable a.

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.

step-by-step explanation: