This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Ophthalmology
Regarding fovea, which of the following statements is true –a) Has the lowest threshold for lightb) Contains only conesc) Contains only rodsd) Maximum visual acuitye) Is located at apex of optic nerve 
Select and explain. 
A. acd, B. bcd, C. abc, D. abd
D: abd
Answer: D: abd 
Explanation: Fovea centralis contains only cones; therefore, has maximum visual acuity and lowest threshold for light.
Option d is absurd as there is no apex in the optic nerve. It is orbital apex where the optic nerve enters the eye socket.