Final answer:
ETI, or Effector-Triggered Immunity, is a plant defense strategy that responds to specific pathogen effectors option (C), leading to programmed cell death and the hypersensitive response to confine pathogen spread.
Step-by-step explanation:
Effector-Triggered Immunity (ETI) is a plant defense mechanism that responds to specific pathogen effectors option (C). ETI is a component of the plant's immune response leading to a hypersensitive response (HR) and programmed cell death to restrict pathogen spread. The interactions between transcription factors and regulatory proteins such as NPR1, bZIP, and MAP kinases are key in modulating plant transcription factors that govern the expression of genes in response to biotic stress. These interactions play a critical role in plant defense mechanisms, signifying a complex web of signal transduction pathways that enhance the plant's ability to withstand environmental challenges. ETI functions through various mechanisms such as inactivation, subcellular localization, degradation, and post-translational modification of transcription factors, ultimately affecting the gene expression related to plant defenses.