Correct

低缓

/ dīhuǎn / 
Strokes

Definition

low and unhurried (voice etc)/low and gently sloping (terrain)

Example

As an Adjective

(of voice) deep and slow

1
Tā
他
dī
低
huǎn
缓
de
的
gēshēng
歌声
yuèěr
悦耳
dòngtīng
动听
  
。

His low and unhurried singing is very pleasant to the ear.

As an Adjective

(of terrain) low and sloping gently

2
Dìshì
地势
dī
低
huǎn
缓

low and gently sloping terrain