题目

通读下面短文，掌握其大意，然后在各题所给的四个选项（A、B、C和D）中选出一个最佳选项。April Fool's Day April Fool's Day is a western festival. No one1 exactly when and how April Fool's Day began. However, there are some stories about2 it came into being. One story3 like this: in the sixteenth­century France, the start of the new year was on April first. It was celebrated 4much the same way 5 it is today with parties and dancing into the late hours of the night.Then in 1562, Pope (教皇) Gregory introduced a new calendar for the Christian world, and the n已知函数f(x)＝4x3＋3tx2－6t2x＋t－1，x∈R，其中t∈R.①当t＝1时，求曲线y＝f(x)在点(0，f(0))处的切线方程；②当t≠0时，求f(x)的单调区间．