what substances play an important role in communication between cells in a multicellular organism by acting as a chemical message

The correct answer is - ligands such as hormones and neurotransmitters.

Explanation:

Communications between the cells of the unicellular organisms take place by the chemical signaling and the substances that help in sending chemical signals between cells are called ligands.

A ligand is a chemical molecule that binds with a specific molecule or a specific signaling receptor, a protein in or on the target cell. Hormones and neurotransmitters are the ligands that help in cell signaling and send chemical messages to the target sites.

i think it's c. i'm not sure but i think so.

un recipient conține 6,4 moli de gaz. gazul hidrogen reprezintă 25% din totalul kilometrilor din container. în cazul în care presiunea totală este de 1.24 atm ceea ce este