Question

which is one of the six fundamental elements that are found in living organisms?
○ helium
○ sodium
○ oxygen
○ chlorine

Explanation:

The six fundamental elements in living organisms are carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur. Among the options, helium is a noble gas not essential for living organisms, sodium is a trace element (not one of the six fundamental), chlorine is also a trace element. Oxygen is one of the six fundamental elements.

Answer:

oxygen (the option with "oxygen" as the text, assuming the options are presented as:

• helium
• sodium
• oxygen
• chlorine

So the correct option is the one labeled with oxygen, e.g., if the options are A. helium, B. sodium, C. oxygen, D. chlorine, then the answer is C. oxygen)