Cotyledons supply nutrients in dicot seeds

Steps:

• Examine the diagram of a dicot seed section to identify key structures like cotyledons, testa, and embryo.
• Recall that dicot seeds rely on stored food reserves for initial growth post-germination.
• Determine which structure holds the endosperm or starch/protein reserves.
• Confirm cotyledons absorb and store these nutrients during seed development.

Why A is correct:

• Cotyledons serve as the primary food storage organs in dicot seeds, providing carbohydrates, proteins, and oils to fuel embryo growth until photosynthesis begins.

Why the others are wrong:

• B (testa): Forms the protective seed coat but contains no nutrients.
• C (embryo): Consumes nutrients rather than storing them for growth.
• D (hilum): Acts as a scar from placental attachment, with no storage role.

Final answer: A