with Father’s Day around the corner, I have taken some money out of the bank_______presents for my dad

A buy    B.to buy     C buying      D to have bought

孙中山建议国史院修撰《国史前编》时“欲至其详细，当从海外各地再行收集材料，乃可呈采。”“若里居、生殁、婚异，凡为群之众，非家乘（注：族谱）一无所稽焉……家乘所详，视官史且信”。孙中山意在强调

A．民间史料比官方史料信度高

B．史料孤证不立，应广搜博采

C．要坚持民生主义的史学观念

D．治史应立足国情并学习西方