The traffic rule says young children under
题型：单项选择题
问题：
The traffic rule says young children under age four and () less that 40 pounds must be in a child safety seat.
A. being weighed
B. to weigh
C. weighed
D. weighing
The traffic rule says young children under age four and () less that 40 pounds must be in a child safety seat.
A. being weighed
B. to weigh
C. weighed
D. weighing