Definition check: in plant tissue culture, “synthetic seeds” are best defined as:

Introduction / Context:
The term “synthetic seed” can be confusing outside plant biotechnology. It specifically refers to encapsulated somatic embryos, not simply to any artificial or GM-derived seed product.

Given Data / Assumptions:

• Somatic embryos arise through tissue culture techniques.
• Encapsulation matrices include alginate gels with additives (nutrients, growth regulators).
• The aim is seed-like handling and potential sowing without full in vitro steps.

Concept / Approach:
By embedding a viable embryo in a gel bead, one obtains a unit that mimics a seed functionally (protection, handling) even without a natural seed coat or endosperm. This is distinct from GM seed, which is a zygotic product bearing a transgene.

Step-by-Step Solution:

Verification / Alternative check:
Protocols universally describe synthetic seeds as encapsulated somatic embryos; the definition is consistent across species.

Why Other Options Are Wrong:

• A: Lacks a living embryo.
• C: GM seeds are natural seeds with transgenes, not encapsulated embryoids.
• D/E: These are other propagules, not encapsulated somatic embryos.

Common Pitfalls:
Using “synthetic seed” as a catch-all term for any nontraditional propagule.

Final Answer:
Somatic embryos encapsulated in a suitable protective matrix