[单选题]
At what temperature are thesxv wm (jhs-s0jyt(* ( m,dr:e numericaiwl8jit6 na)d-mvvuly jg ;8t0+t8*ql readings on the Fahrenheit and Celsius scales th a8*ijy6 q+ vmt0jt;ugv-ldwl88i) nte same?
A. $-30^{\circ}$
B. $-40^{\circ}$
C. $-50^{\circ}$
D. $-60^{\circ}$
