Question

Where do I place commas in this sentence;

Snails barnacles coral and sea urchins produce their rigid parts by combining calcium
and carbonate ions.

Answer 1

Snails, barnacles, coral, and sea urchins produce their rigid parts by combining calcium and carbonate ions.

Answer 2

Snails, barnacles, coral, and sea urchins produce their rigid parts by combining calcium and carbonate ions.