Correct

化为灰烬

/ huā wéi huījìn /
Strokes

Example

Definition

turn to dust and ashes; be consumed by fire; be reduced/burned to ashes

1
huǒ
大火
shǐ
使
zi
屋子
de
suǒyǒu
所有
dōng
东西
dōu
huāwéihuījìn
化为灰烬
  

Everything in the house was consumed by the big fire.