患者男，4岁半，全牙列反<img src="/Image1/45/4539efd5dc2648d2aba70d3c0615c414.jpg" />，父亲是反<img src="/Image1/45/4539efd5dc2648d2aba70d3c0615c414.jpg" />面型。上前牙唇倾度正常，下前牙直立，反覆盖5mm，反覆<img src="/Image1/45/4539efd5dc2648d2aba70d3c0615c414.jpg" />浅。该患者反<img src="/Image1/45/4539efd5dc2648d2aba70d3c0615c414.jpg" />形成的可能机制是（）。<br>A:遗传<br>B:上颌骨发育不足<br>C:下颌骨发育过度<br>D:上颌骨发育不足，下颌骨发育过度<br>E:功能性前牙反<img src="/Image1/45/4539efd5dc2648d2aba70d3c0615c414.jpg" />