- A Mainly vessels and tracheids, with very few living cells present
- B Sieve tubes, companion cells, phloem fibres, and phloem parenchyma
- C Mainly sieve tubes, with relatively few associated companion cells
- D Vessels, companion cells, and sclerenchyma fibres combined together
Correct answer: B. Sieve tubes, companion cells, phloem fibres, and phloem parenchyma
Explanation: Phloem has four components: (1) Sieve tube elements - main conducting cells with sieve plates; (2) Companion cells - regulate sieve tubes; (3) Phloem fibres - support; (4) Phloem parenchyma - storage.
Concept context
Internal tissue organisation: meristems, permanent tissues (xylem, phloem, parenchyma), and secondary growth. Frequently tested in NEET.