The correct answer is option 1: between 150 and 200 mg. Blood cholesterol level refers to the amount of cholesterol present in 100 ml of blood. Cholesterol is a fatty substance found in the body and is necessary for various bodily functions. However, high levels of cholesterol can lead to health problems like heart disease. In a normal person, the blood cholesterol level typically falls within the range of 150 to 200 mg. This range is considered to be a healthy level for cholesterol. It is important to maintain a balanced diet and lifestyle to keep cholesterol levels within this range. Regular exercise, a healthy diet low in saturated and trans fats, and avoiding smoking are all important for maintaining healthy cholesterol levels.