单项选择题

The experience of dealing with a clamorous band of younger siblings, earning their affection while holding them to their tasks, can prove remarkably______in later years when one deals with______colleagues jealous of their prerogatives.()

A、 useful… fractious
B、 trenchant … ambitious
C、 deep-seated … difficult
D、 prophetic… envious
E、 truculent… unruly