a. hemoglobin
b. insulin'
c. lactase
d. keratin
e. testosterone

???

but it is not a protein.

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testosterone is not a protein duh it's a hormone and sugar IS a protein i took bio last semester

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Sugar is not a protein.  Sugars are molecules made up of small numbers of building blocks called saccharides - normal sugar as used in baking is sucrose, which is a disaccharide (ie it is composed of two saccharides).  Chemically, a saccharide consists of a central ring of carbon atoms with oxygen and hydrogen atoms bonded on around the outside.

Proteins are made up of building blocks called amino acids, and are much larger molecules.  As well as carbon, oxygen and hydrogen, they also contain nitrogen.

You are, however, correct that testosterone is not a protein, though this is not because it's a hormone - insulin, which is a protein, is also a hormone - incidentally this is the reason diabetics cannot simply take insulin pills: the body would just digest the insulin.  Testosterone is a steroid, which is a different class of chemicals again.