Answer:
cholesterol.
Explanation
Options a, d, c, and e all contains amino acids units. They are therefore made up of protein structure. cholesterol contains alcohol and steroids. it belongs to the steroid lipid family unlike other options that belong to protein family.
Human forelimbs is used for a variety of functions, such as for eating.
Similarities: They are all made from the same basic anatomical structure classified as homologous structures.
They all have this structure inherited from a common ancestor.