To solve this problem, we need to identify which of the given options is not a steroid hormone. Let's analyze each option:$\newline \bullet$Progesterone:$\newline$ - Progesterone is a steroid hormone involved in the menstrual cycle, pregnancy, and embryogenesis.$\newline$ - It is synthesized from cholesterol and belongs to the class of steroid hormones.$\newline \bullet$Glucagon:$\newline$ - Glucagon is a peptide hormone produced by the alpha cells of the pancreas.$\newline$ - It plays a crucial role in glucose metabolism by promoting the conversion of glycogen to glucose in the liver.$\newline$ - Unlike steroid hormones, glucagon is not derived from cholesterol.$\newline \bullet$Cortisol:$\newline$ - Cortisol is a steroid hormone produced by the adrenal cortex.$\newline$ - It is involved in the regulation of metabolism and the immune response.$\newline$ - Cortisol is synthesized from cholesterol, classifying it as a steroid hormone.$\newline \bullet$Testosterone:$\newline$ - Testosterone is a steroid hormone that plays a key role in the development of male reproductive tissues and secondary sexual characteristics.$\newline$ - It is synthesized from cholesterol and is part of the steroid hormone family.$\newline$Based on the analysis, glucagon is the only hormone that is not a steroid hormone.$\newline$Therefore, the correct option is Option 2: Glucagon.