On Physical Examination, You Notice That a Patient Has Tendon

On physical examination, you notice that a patient has tendon xanthomas.A blood analysis reveals a total cholesterol level of 350 mg/dL, which results mainly from raised levels of LDL, and normal levels of triglyceride.What other investigation would be helpful in this patient?

A) Look for eruptive xanthomas.
B) Perform a VLDL analysis.
C) Isolate the patient's lymphocytes and measure the number of LDL receptors.
D) Check for hyperthyroidism.
E) Measure fasting blood glucose.