[单选题]
A container of an id wp4(pad98,m bsn n:dzeal gas at 1 atm is compressed to one-third its volume, with(a498znpw ,:mbsd dpn qe b 6asagy:6: the temperature held constant.b seagq: 6y:a6 What is its final pressure?
A. $1/3 \; atm$
B. $1 \; atm$
C. $3 \; atm$
D. $9 \; atm$
