[单选题]
Consider a closed pipe of length L. What are the wago u6q vt;/kj+5novt.velengths of the three+6.,bfhuqdqgu* d hkv( n ;5ub lowest tonesu;uh*uh n bd q,qb5d (.k6+gvf produced by this pipe?
A. 4L, 2L, L
B. 2L, L, L/2
C. 2L, L, 2L/3
D. 4L, 4L/3, 4L/5
