The organelle that is the most numerous and the site of protein synthesis is the ribosome.

Here's why:

* Most Numerous: Ribosomes are found in vast numbers within cells, especially those actively producing proteins. They can be found free-floating in the cytoplasm or attached to the endoplasmic reticulum.

* Protein Synthesis: Ribosomes are the molecular machines responsible for translating the genetic code from messenger RNA (mRNA) into proteins. They read the mRNA sequence and assemble amino acids into polypeptide chains, which fold into functional proteins.

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