Answer:
Chemical inhibitors likely bind to receptors and interfere with receptor activation or signal-receptor binding.
Explanation:
The signaling pathway requires the generation of a signal, its reception by target cells, signal transduction and cellular response. According to the given information, the inhibitors are the large and non-polar molecules. The cell membranes do not allow free passage of large molecules. Therefore, these inhibitors are most likely to interfere with signal reception by target cells.
For the purpose, the inhibitors may bind to the receptors present on the surface of target cells and thereby, not allowing the binding of the signaling molecule to the receptors and the activation of the receptors. Unless the signaling molecule binds to its receptors present on the surface of target cells, receptors remain inactive and there is no signal transduction.