During an allogeneic organ transplant, the recipient's T-lymphocytes recognize the donor's Major Histocompatibility Complex (MHC) molecules as foreign, leading to acute graft rejection. Which of the following statements accurately explains the immunological basis of this phenomenon (alloreactivity)?

Options:

• A: Donor MHC molecules are structurally identical to recipient MHC molecules but carry different lipid antigens.
• B: Donor B-cells secrete antibodies that specifically target and destroy recipient MHC Class I molecules.
• C: Recipient CD4+ T-cells directly lyse donor cells without requiring MHC recognition.
• D: Recipient T-cell receptors (TCRs) cross-react with foreign donor MHC molecules presenting self or donor peptides, mimicking self-MHC/foreign peptide complexes.

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