[单选题]
The energy gap between the valeztiw*1zy ),jvs l u64kncm5u51 koyjz162tjv nge and conduction bands in a certain semiconductor is 1.25 eV. What is the threshold wavelengt 26y55v 1j1tmgonzujk h for optical absorption in this substance?
A. $599 \; nm$
B. $959 \; nm$
C. $873 \; nm$
D. $995 \; nm$
