Which statement best explains why the cornea remains avascular during development?

• A. Anti-angiogenic environment maintains corneal avascularity during development
• B. High levels of VEGF in the cornea
• C. Dense vascular network from conjunctiva
• D. Blood vessels form then regress early in development

Answer: (A)

The main idea is that the cornea stays clear because it actively keeps blood vessels from growing there. During development, corneal tissues create an anti-angiogenic environment—they secrete factors that inhibit new vessel formation and neutralize pro-angiogenic signals like VEGF. This balance prevents vascular invasion from the surrounding conjunctival network and preserves corneal transparency essential for vision. If pro-angiogenic signals outweighed the inhibitors, vessels could invade and cause opacities, which is not the normal developmental pattern. So maintaining an anti-angiogenic milieu explains why the cornea remains avascular.