下列哪种情况不属于沉管灌注桩的质量问题：（    ）

A、<span style="FONT-FAMILY: 宋体; FONT-SIZE: 14px">缩颈</span>

B、<span style="FONT-FAMILY: &#39;Times New Roman&#39;,&#39;serif&#39;; FONT-SIZE: 14px">.</span><span style="FONT-FAMILY: 宋体; FONT-SIZE: 14px">吊脚桩</span>

C、<span style="FONT-FAMILY: 宋体; FONT-SIZE: 14px">桩靴进水</span>

D、<span style="FONT-FAMILY: &#39;Times New Roman&#39;,&#39;serif&#39;; FONT-SIZE: 14px">.</span><span style="FONT-FAMILY: 宋体; FONT-SIZE: 14px">混凝土质量降低</span>