c
(c)
$\frac{d^2 y}{d x^2}$ will have dimensions of $\frac{y}{x^2}$
$y \rightarrow$ pressure, $x \rightarrow$ velocity gradient
$x \rightarrow \frac{V}{L} \Rightarrow \frac{ LT ^{-1}}{ L } \Rightarrow T ^{-1}$
$\frac{y}{x^2}=\frac{ ML ^{-1} T ^{-2}}{ T ^{-2}} \Rightarrow\left[ ML ^{-1}\right]$