What Is Thought to Be the First Major Derived Feature

What is thought to be the first major derived feature that separates land plants from charophytes?

A) Both charophytes and land plants have chlorophyll b,but only land plants have chlorophyll a.
B) Both charophytes and land plants store excess carbohydrates,but only land plants use glucose.
C) Both charophytes and land plants protect their zygotes,but only land plants also protect the resulting embryo.
D) Both charophytes and land plants are made up of cells,but only land plants have cell walls.
E) Both charophytes and land plants have cell walls,but only land plants use cellulose in their cell walls.