this boy______(have)shorter hair than his hair用have的正确形式填空

this boy______(have)shorter hair than his hair用have的正确形式填空
this boy______(have)shorter hair than his hair
用have的正确形式填空

this boy______(have)shorter hair than his hair用have的正确形式填空
has

has had

has
考点应该是have的第三人称单数形式吧
好象没什么复杂的内容吧