• Statement (I) is False: Chloroplasts are fully differentiated, highly active photosynthetic plastids; chromoplasts and gerontoplasts typically represent terminal, non-photosynthetic or degenerative plastid stages.
• Statement (II) is True: According to the Endosymbiotic Theory (Lynn Margulis), chloroplasts originated from ancestral photosynthetic cyanobacteria engulfed by early eukaryotic cells, retaining a circular genome, 70S ribosomes, and a double-membrane envelope.
• Conclusion: Statement (I) is false but Statement (II) is true.

Correct option: (4) Statement (I) is false but Statement ({I) is true.

• Assertion (A) is True: Plasmodesmata are membrane-lined cytoplasmic bridges traversing plant cell walls, creating microscopic pores that establish symplastic continuity across adjacent cells.
• Reason (R) is True & Explains (A): Primary plasmodesmata form during cytokinesis as tubules of the endoplasmic reticulum (desmotubules) become entrapped across the fusing cell plate. Polysaccharide matrix and cellulose microfibrils are physically prevented from depositing at these localized junctions, preserving the pore channel.
• Conclusion: Both (A) and (R) are true and (R) is the correct explanation of (A).

Correct option: (1) Both (A) and (R) are true and (R) is the correct explanation of (A)

• Statement (I) is False: The nuclear envelope is a double-membrane barrier that is an uninterrupted subdomain of the endoplasmic reticulum (ER)—its outer membrane is continuous with the rough ER and studded with ribosomes, not the Golgi complex.
• Statement (II) is True: Nuclear pore complexes (NPCs) span both the inner and outer nuclear membranes, forming aqueous selective transport channels that regulate nucleocytoplasmic macromolecular trafficking (proteins, mRNA, ribonucleoprotein complexes).
• Conclusion: Statement (I) is false but Statement (II) is true.

Correct option: (4) Statement (I) is false but Statement ({I) is true.

• Root Meristem Organization: In the Arabidopsis root apical meristem:
• The Quiescent Center (QC) acts as the stem cell organizer.
• Positioned directly distal (below) to the QC are the columella initials, which divide to generate the central root cap (columella) containing starch statoliths.
• Cortical-endodermal initials flank the QC laterally, while stele initials are located proximal (above) the QC.

Correct option: (4) Columella initials