这两天看了这个问题，很不解，尤其是今天当原问人把Beachy 老师的答案选为最佳答案。有三位专家老师都认为选the。 我想请原问人及Beachy 老师详细说明理由，可以吗？先谢谢。不是在挑刺，是实在不解，请原谅。

附原问问题：

下面是孩子辅导班的一道完形填空的最后一段： Father Christmas spoke to every one of them. At last it wasmyturn,"Hello, little Tom," he said to me. As soon as I heard_______voice I found out that he was my uncle, John Smith. A. the B. his C. aD. / 老师说选B，我认为选A也对。请教老师，老师回答说选A也对，但应优先选B。可是我觉得似乎应优先选A，感觉此处似乎应为特指，但好像又不是。是A、B皆可，还是只能选其中之一？请指教，谢谢！