Which of the following best describes lineal consanguinity?

Lineal consanguinity refers to a direct blood relationship between individuals through direct ascendants and descendants. This includes parents, grandparents, children, and grandchildren, all of whom share a straight lineage. The correct response captures the essence of lineal descent, which is characterized by a direct line of ancestry.

Ancestors, while they represent the lineage, do not encompass the full scope of lineal relationships since it is focused on both ascendants and descendants. Collateral relatives, such as cousins, aunts, and uncles, branch off from the direct lineage and do not fit under the definition of lineal consanguinity. Family by marriage, such as in-laws, highlights a relationship not constructed through blood but rather through marital connections, thus distinguishing it from consanguinity.