HSK C6
Correct

祖

/ zǔ / 
Strokes

Definition

ancestor/forefather/grandparents

Example

As a Noun
ancestor
1
Yuǎn
远
zǔ
祖

remote ancestors

As a Noun
grandfather
2
Gāozǔ
高祖

great grandfather

As a Noun
founder (of a craft, religious sect, etc); originator