[单选题]
When a tube of diameter d e:nz: v vp7 etl :t3rw,5dotn qz-c5k5is placed in waterik3z7pw*w,l1jl a,msz s2j;nph-ko(, the water rises to a height h. If the diamete a2z1klppz 73w lh*jomk;sw, -snj,(ir were half as great, how high would the water rise?