Which sentence correctly uses the subjunctive mood in legal context?

What is the expected change in the number of males and females in the reproducing age group due to the change in male mortality rates?

在计算机科学中，以下哪个选项最能描述'算法'的基本概念？

已知数列 a_n = 2n + 1，求 a_5 的值。

设函数f(x)在区间[a, b]上连续，且f(a) > 0，f(b) < 0，则根据介值定理，下列结论正确的是：