[单选题]
A closed organ pipe of ,rrjrhjxorr8n,) (j 4,p h2hawj 5u hw,m sxi:dg;,5: lbbn,hlength 0.75 m is played when the speed of sound in air is 340 m/s. What is the fundamental ;lxhd5 h,h5:wn2m,guba,, jws: i bhp frequency?
A. $57 \; Hz$
B. $113 \; Hz$
C. $170 \; Hz$
D. $227 \; Hz$
