What defines a gas permeable contact lens and how does its material influence oxygen transmission compared with traditional soft hydrogel lenses?

What defines a gas permeable contact lens and how does its material influence oxygen transmission compared with traditional soft hydrogel lenses?

• A. A gas permeable lens is a rigid lens made with silicone-containing polymers that allow oxygen to pass through more readily.
• B. Gas permeable lenses are flexible and rely on water to deliver oxygen.
• C. GP lenses have lower Dk/t than traditional hydrogel soft lenses.
• D. GP lenses do not allow oxygen and depend on tear exchange only.

Answer: (A)