[单选题]
How long will it takrp;4bc t hk/))xug sh2sb.1;aeozi9 g7p9- y t/de .zkzs8qsue a $4.5 \; Ci$ 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. $1993 \; years$