Answer: The answer is (d) the circumference is found by multiplying pi by the diameter.
Step-by-step explanation: We are to select the correct statement from the given options that are true about the circumference of a circle.
We know that the circumference 'C' of a circle is given by
![C=2\pi r,](https://img.qammunity.org/2019/formulas/mathematics/middle-school/dzu1l3mycpt3z1uhklbp4xfxiin451mqax.png)
Where 'r' is the radius of the circle.
So, 2r = diameter of the circle.
Therefore, the circumference is found by multiplying pi by the diameter of the circle.
Thus, (d) is the correct option.