[单选题]
How long will it takeh:,ndg wezr qsq ya *+r61so-2 a 65k,1 ag0qblk 7j6nafw k5tv r$4.5 \; Ci$ sample of material to reach an activity level of $0.14 \; Ci$ if the half-life is 435 years?
A. $14,478 \; years$
B. $3245 \; years$
C. $2178 \; years$
D. $1993 \; years$
