Answer:
B.
[tex]from \: eisteins \: energy \: relation : \\ E = hf \\ h \: is \: plancks \: constant\\ 3.26 \times {10}^{ - 19} = 6.63 \times {10}^{ - 34 } \times f \\ f = \frac{3.26 \times {10}^{ - 19} }{6.63 \times {10}^{ - 34} } \\ f = 4.92 \times {10}^{14} \: Hz[/tex]