Which substance indicates that green algae and plants form monophyletic lineage?

Explanation

The correct answer is Genetic material. Genetic material, particularly DNA sequences, is used to trace evolutionary relationships and demonstrates that green algae and plants share a common ancestor, forming a monophyletic lineage. This shared genetic heritage is a more definitive indicator of their evolutionary relationship than other substances like lipids, proteins, or carbohydrates, which are present in many different organisms and do not specifically indicate common ancestry.