国有、集体企业出售，被出售企业法人予以注销，并且买受人妥善安置原企业30%以上职工的，对其承受所购企业的土地、房屋权属，免征契税。 ( )

On April 24, Tsinghua University         its 100^th anniversary at the Great Hall of the People in Beijing.

A．congratulated

B．challenged

C．celebrated

D．participated