学校举办的强身健体活动周上，开设田径、球类、体操三大项，要求每位同学至少参加一项，最多参加两项．某班有18名同学参加了田径项目，12名同学参加了球类项目，25名同学参加了体操项目，那么这个班级最多有______人，最少有______人．

The process of establishing clear and achievable objectives, measuring their achievement, and adjusting performance in accordance, with the results of the measurement is called ______ .

A．strategic planning

B．alternative objectives inventory

C．management by objectives

D．contingency planning