Final answer:
The RTKs pathway involves tyrosine phosphorylation of receptors, not activation of G-proteins, use of serine/threonine kinases, or inhibition of kinase cascades.
Step-by-step explanation:
The question is regarding the RTKs (Receptor Tyrosine Kinase) pathway which is a crucial component of cellular signaling. The correct answer is C. Tyrosine phosphorylation of receptors. Receptor Tyrosine Kinases (RTKs) are enzyme-linked receptors with a single transmembrane region and both extracellular and intracellular domains. They play a significant role in cell division by responding to growth factors. Upon the binding of a signaling molecule, RTKs undergo dimerization. This leads to autophosphorylation of tyrosine residues within the intracellular domain, which then triggers subsequent cellular responses. These responses can include activating a series of kinases in a cascade, often involving the MAP kinase pathway, which can result in changes such as cell division.