Correct

改色

/ gǎi sè / 
Strokes

Example

As a Verb

change in colour

1
Xià
夏
qiū
秋
jiāotì
交替
zhījì
之际
shùmù
树木
gǎi
改
sè
色
  
。

The trees change in colours when summer is changing into autumn.

As a Verb

change/turn colour