The closest algal relatives of land plants are __________.

• A. red algae
• B. brown algae
• C. chlorophytes
• D. charophytes

Answer: (D)

Verified step by step guidance

1. Understand the context: Land plants evolved from aquatic ancestors, and their closest relatives are algae. To determine the closest algal relatives, we need to examine evolutionary relationships and shared characteristics.
2. Review the options: Red algae, brown algae, chlorophytes, and charophytes are all types of algae. Each group has distinct features and evolutionary histories.
3. Eliminate unrelated groups: Red algae and brown algae are more distantly related to land plants. They belong to different evolutionary lineages and lack key traits shared with land plants.
4. Compare chlorophytes and charophytes: Both are green algae and share some traits with land plants, such as chlorophyll a and b. However, charophytes have additional similarities, including the presence of specific proteins involved in cell division and the structure of their flagellated sperm.
5. Conclude that charophytes are the closest relatives of land plants based on shared traits and evolutionary evidence, such as similarities in cell wall composition and genetic data.