Correct

低层

/ dī céng / 
Strokes

Definition

low level

Example

As a Noun

lower storey/floor

1
Wǒ
我
yīzhí
一直
zhù
住
zài
在
dī
低
céng
层
  
。

I have been living on one of the lower floors.

As a Noun

low grade/rank/level

2
Dī
低
céng
层
zhíyuán
职员

low-ranking office worker

3
Dī
低
céng
层
jiējí
阶级

lower class

4
Dī
低
céng
层
huìyì
会议

low-level meeting