Inis question: $1$ point$($s$)$ possible

Ford Motor Company had realized retums of $5\%,15\%,-15\%,$ and $-5\%$ over four quarters. What is the quarterly standard deviation of retums for Ford?

A$.12\mathrm{.}91\%$

B$.12\mathrm{.}26\%$

C$.11\mathrm{.}62\%$

D$.10\mathrm{.}97\%$