Seed plants are divided into

Analyze the question: It asks how seed plants (spermatophytes) are divided at the highest level, meaning the two main groups of plants that produce seeds.

Explain the concept: Plants that reproduce by seeds are called spermatophytes. They are split into two major groups based on how their seeds are protected:

• Gymnosperms ("naked seeds"): the seeds are not enclosed in an ovary or fruit. Examples are pine, cycads and cedar, which bear cones.
• Angiosperms (flowering plants): the seeds are enclosed in a fruit that develops from the ovary. Examples are mango, maize, beans and orange.

Step-by-step solution:

• A. Tracheophytes and ferns: Wrong. Ferns are themselves tracheophytes (vascular plants), and they reproduce by spores, not seeds.
• B. Angiosperms and gymnosperms: Correct. These are the two divisions of seed plants.
• C. Monocotyledons and dicotyledons: These are the two subdivisions of angiosperms only. They do not include gymnosperms, so they cannot be the main division of all seed plants.
• D. Thallophytes and bryophytes: Wrong. Neither group produces seeds. Thallophytes include algae and fungi, and bryophytes include mosses and liverworts.

Answer: B. Angiosperms and gymnosperms.

Exam tip: Remember the plant ladder: Thallophytes → Bryophytes → Pteridophytes (ferns) → Spermatophytes (gymnosperms and angiosperms). Only the last group makes seeds. Also, watch out for option C. It is a common trap, because monocots and dicots divide only the angiosperms.