OFFICIAL EXPLANATION


Peter takes 2 minutes to walk along the circumference of the semi circle i.e. Peter covers $\(\frac{1}{2}(2 \pi r)=\pi r\)$ distance in 2 minutes, so the average speed of Peter is $\(\frac{ Distance }{ Time }=\frac{\pi r}{2}\)$

Also it is given that Beth takes 1 minute to travel along the diameter of the semi circle i.e. Beth covers \(2 r\) distance in 1 minute, so the average speed of Beth is $\(\frac{ Distance } {Time }=\frac{2r}{1}=2r\)$

Clearly $\(\frac{\pi r}{2}=\frac{22}{7 \times 2}(\mathrm{r})=\frac{22}{14}(\mathrm{r})\)$ is less than $\(2(\mathrm{r})\left(\right.$ As $\left.\frac{22}{14}=1.57<2\right)\)$
Hence column $\(B\)$ has higher quantity, so the answer is (B).