A particle p moves from the point $\mathrm{A}(0,4)$ to the point $(10,-4)$. The particle P can travel the upper-half plane $\left\{(\mathrm{x},\mathrm{y})|\mathrm{y}\ge 0\right\}$ at the speed of 1 m/s and the lower-halfplane$\left\{(\mathrm{x},\mathrm{y})|\mathrm{y}\le 0\right\}$ at the speed of 2 m/s. The coordinates of a point on the x-axis, if the sum of the squares of the travel times of the upper- and lower-half planes is minimum, are

• A

  $(1,0)$

• B

  $(2,0)$

• C

  $(4,0)$

• D

  $(5,0)$