[单选题]
The average life of an animalt6p 9wlua.,g+v v 3qqy issq6j8 ;l lqc9ci)(to q 70 years. Assume one numerical figure, write this8l9 i;jtcqq)6 qocl(s in power of ten in seconds.
A. $3 \times 10^{7} \; s$
B. $2 \times 10^{7} \; s$
C. $2 \times 10^{9} \; s$
D. $3 \times 10^{9} \; s$
