In the past half-century, average incomes _______ quickly in developed countries, yet happiness levels have remained almost the same.

A．have risen

B．had risen

C．rose

D．rise

各道段投递人员领取补章单后，必须在（）天内完成补章手续（遇有特殊情况，须经上一级主管人员批准），不得随意延长补章时限。