Final answer:
Hydrophobic chemical messengers can indeed travel through cell membranes due to their compatibility with the hydrophobic interior of the lipid bilayer. The correct option is A.
Step-by-step explanation:
The statement that hydrophobic chemical messengers can easily travel through cell membranes is true. Hydrophobic molecules are able to pass through the plasma membrane with ease if they are small enough, due to their ability to interact with the hydrophobic (water-hating) interior of the lipid bilayer.
This is in contrast to hydrophilic (water-loving) molecules, which cannot pass through the hydrophobic core of the plasma membrane without assistance. Steroid hormones, for example, are hydrophobic and can thus readily diffuse across the membrane.
This process is crucial for the regulation of gene expression as many of these hormones bind to intracellular receptors that act as transcription factors.