○=> Correct option :
[tex]\color{plum}\tt\bold{(B)}[/tex]
○=> Steps to derive correct option :
We know that :
[tex]\color{hotpink} \tt \: circumference \: of \: a \: circle\color{plum} = 2\pi r[/tex]
So, let the diameter of this circle be x.
Which means :
[tex] =\tt2 \times \pi \times r[/tex]
[tex] =\tt 2 \times x \times \pi = 12\pi[/tex]
[tex] =\tt 2x\pi = 12\pi[/tex]
[tex] =\tt x = \frac{12}{2} [/tex]
[tex] = \tt \: x = 6 \: m[/tex]
Thus, the radius of the circle Robert drew = 6 m
Since the circle in option B has a radius of 6 m, it is the circle Robert drew.
▪︎Therefore, the correct option is (B)
