why Joseph and not Mary?

with the geneology of Jesus, why do they use Joseph’s geneology instead of Mary’s. Mary is Jesus biological mother where Joseph is not the biological father?

The following links should assist you in better understanding the Catholic Church’s teaching on Jesus’ geneology. If you have any further questions or concerns that are not answered by these links, please contact Catholic Answers directly.**Recommended Reading:
[LIST]
*]If Joseph isn’t Jesus’ father, how can Jesus be the Son of David?
*]**Do we know for certain the Blessed Mother’s lineage? **
*]Do we know Jesus’ genealogy?
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