根据第三段第二句“The pupils often work in groups：this gives them the opportunity to learn to cooperate，to share，and to develop leadership skills.”可知，经常以小组学习的学生们可以有机会学会合作、分享，以及培养领导能力。由此，可以分别对应到选项A、C。根据第三段第三句“They also learn how to cope with personalproblems as weII as learning how to think.…”可知，学生们以小组学习可以学到如何处理个人问题，而且还可以学会如何思考等，可与选项B“reasoning abilities”(推理能力)相对应。因此，通过排除可以得到本题答案为D。