西周时期规定用鼎制度为“天子九鼎，诸侯七鼎，大夫五鼎”。这反映了当时社会结构的突出特点是 [ ]

A、血缘与政治结合

B、社会等级严格

C、中央集权加强

D、青铜制造业发达

Just as there are occupations that require college degrees also there are occupations for which technical training is necessary.

A．so to there are

B．so too there are

C．so there are

D．so too are there