Question

select the element that is found in proteins but not found in carbohydrates or lipids. carbon (c) sulfur (s) nitrogen (n) hydrogen (h) carbohydrate lipid protein

Explanation:

Carbohydrates are composed of carbon (C), hydrogen (H), and oxygen (O). Lipids mainly contain carbon (C), hydrogen (H), and oxygen (O). Proteins are made up of carbon (C), hydrogen (H), oxygen (O), nitrogen (N), and sometimes sulfur (S). Nitrogen is present in proteins (in the amino - group of amino acids) but not in carbohydrates or lipids in significant amounts. Carbon and hydrogen are common to all three, and sulfur is not a universal component of proteins and is definitely not the key differentiating element here.

Answer:

C. nitrogen (N)