The work function for tungsten is 4.58 eV. Of the following, which is the best estimate of the threshold frequency required for the emission of photoelectrons from a tungsten cathode?
(A)0.1x10¹⁵Hz
(B)0.5x10¹⁵Hz
(C)1x10¹⁵Hz
(D)2x10¹⁵Hz
(E)3x10¹⁵Hz