Which Statement Best Describes the Action of Polypeptide Growth Factors

Multiple Choice

Which statement best describes the action of polypeptide growth factors?

A) They bind to intracellular receptors and trigger intracellular signal transduction pathways.
B) They bind to cell surface receptors and trigger intracellular signal transduction pathways.
C) They bind to cell surface receptors that phosphorylate cyclins.
D) They bind an intracellular receptor forming a complex that then acts as a transcription factor.