Some Pattern Recognition Receptors (PRRs) recognize nucleic acids, like RNA or DNA. Since our own cells contain human RNA and DNA, the activation of innate immune pathways by these PRRs must rely on additional criteria to discriminate self from nonself. Additional criteria include everything EXCEPT:

Correct Answer: B

Rationale: PRRs distinguish self via RNA location , DNA methylation , and viral RNA structures ; adenosine presence isn't a key discriminator.

Correct Answer: B

Rationale: V-J recombination maximizes CDR3 diversity ; not all cells , not splicing , or precise .

Correct Answer: D

Rationale: Plant hormones like ethylene, gibberellins, and auxins are used to control fruit processes, produce seedless fruits, and act as herbicides. All options are correct.

Correct Answer: D

Rationale: Antibodies are proteins made of polypeptide chains, specific to adaptive immunity, not amino acids, lipids, or carbohydrates.

Correct Answer: D

Rationale: Cytotoxic T cells destroy infected cells via perforin and granzymes, unlike macrophages (phagocytosis), plasma cells (antibodies), or B cells (humoral).