This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Retina, Subject name: Ophthalmology
Trucking of vessels is seen in which of the following disorders 
Select and explain. 
A. Central retinal artery occlusion, B. Central retinal vein occlusion, C. Hypertensive retinopathy, D. Sickle cell retinopathy
A: Central retinal artery occlusion
Answer: A: Central retinal artery occlusion 
Explanation: Ans. (a) Central retinal artery occlusionRef: Kanski 7/e, p. 562Narrowing of arteries and veins with sludging of and segmentation of blood column - Cattle trucking/ Boxcarring.