[单选题]
A 3.00-m long pipe i48s-m9nog*a5d2q j g-o eovhys in wgh ,tzb;n48ja room where the temperature is $20 \; ^{\circ}C$. What is the fundamental frequency if the pipe is closed at one end?
A. $57 \; Hz$
B. $114 \; Hz$
C. $29 \; Hz$
D. none of the above
