(c)
Given, $\frac{dy}{dx} + y.\frac{1}{x}\log x = e^{x}\ x^{- \left( \frac{1}{2} \right)\log x}$
$\therefore$ $IF = e^{\int_{}^{}{\frac{1}{x}\log x\ dx}} = e^{\int_{}^{}\frac{\left( \log x \right)^{2}}{2}} = \left( \sqrt{e} \right)^{\left( \log x \right)^{2}}$