I'd like to know if Lin Tao is the second _____ boy in his class. [ ]

A. older

B. the older

C. oldest

D. the oldest

砌筑每立方米一砖厚砖墙，砖(200mm×150mm×50mm)的净用量为240块，灰缝厚度为10mm，砖的损耗率为1%，砂浆的损耗率为5%。则每立方米一砖厚砖墙的砂浆消耗量为( )m³。

A．0.564
B．0.598
C．0.642
D．0.672