This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Vitreous and retina, Subject name: Ophthalmology
Synchysis refers to 
Select and explain. 
A. Collapse of the vitreous, B. Black spots in front of the eyes, C. Liquefaction of the vitreous, D. Detachment of the vitreous
C: Liquefaction of the vitreous
Answer: C: Liquefaction of the vitreous 
Explanation: VITREOUS LIQUEFACTION (SYNCHYSIS) Vitreous liquefaction (synchysis) is the most common degenerative change in the vitreous. Causes of liquefaction: 1. Degenerations such as senile, myopic, and that associated with retinitis pigmentosa. 2. Post-inflammatory, paicularly following uveitis. 3. Trauma to the vitreous which may be mechanical (blunt as well as perforating). 4. Thermal effects on vitreous following diathermy, photocoagulation and cryocoagulation. 5. Radiation effects may also cause liquefaction. Ref:- A K KHURANA; pg num:-244