This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Radiology
Carotid aery stenosis in -vivo screening choice is 
Select and explain. 
A. USG, B. CT, C. MRI, D. Doppler
D: Doppler
Answer: D: Doppler 
Explanation: Most carotid imaging is now performed with Doppler ultrasound, CTA, MRA performed without exogenous contrast injection such as 2- or 3-dimensional time-of-flight (TOF) methods or contrast-enhanced MRA (CEMRA) performed dynamically after an intravenous bolus of gadolinium-based contrast.CEMRA is the most accurate method of carotid stenosis evaluation(Grainger and Allison&;s diagnostic radiology 6th edition, page 1475)