An incompressible fluid flows over a flat plate with zero pressure gradient. The boundary layer thickness is $1 \mathrm{~mm}$ at a location where the Reynolds number is $1000 .$ If the velocity of the fluid alone is increased by a factor of $4,$ then the boundary layer thickness at the same location, in $m m$ will be
(A) 4
(B) 2
(C) 0.5
(D) 0.25
An incompressible fluid flows over a flat plate with zero pressure gradient. The boundary layer thickness is $1 \mathrm{~mm}$ at a location where the Reynolds number is $1000 .$ If the velocity of the fluid alone is increased by a factor of $4,$ then the boundary layer thickness at the same location, in $m m$ will be
(A) 4
(B) 2
(C) 0.5
(D) 0.25