The energy of an X-ray photon of wavelength $1.65 \mathring{A}$ is : ($h = 6.6 \times 10^{-34} Js, \; c = 3 \times 10^8 ms^{-1}, \; 1eV = 1.6 \times 10^{-19}J$)

Question

( A ) $3.5\; keV$
( B ) $5.5\;keV$
( C ) $9.5\;keV$
( D ) $7.5 \;keV$