The blood glucose level is commonly expressed as

The correct answer is B) Milligram per decilitre (mg/dL). In India's clinical labs, and in most prescriptions and diagnostic reports, fasting blood glucose is reported in mg/dL. A normal fasting value is roughly 70 to 100 mg/dL, and diabetes is diagnosed at 126 mg/dL or more on a fasting test.

• A) mm of Hg is a unit of pressure. It is used for blood pressure, not for concentration.
• C) Parts per million is a dimensionless concentration unit used for trace or environmental levels. It is not the clinical convention for glucose.
• D) Gram per litre is technically a valid concentration unit, and normal glucose is about 0.7 to 1.1 g/L. However, it is not the common clinical convention in India.

The concept here is units of measurement in clinical biochemistry. Note that many countries, including the UK and much of Europe, report glucose in mmol/L (SI units) instead. Keep both conventions in mind, because questions on this topic often test which unit is common rather than which unit is merely possible.

Trap: choosing D because g/L is a valid concentration unit. The question asks for the commonly used unit, not any correct one.