Which among the following is true about Total Internal Reflection?

• A. A ray passing from rarer to denser medium and not able to pass to denser medium at an angle greater than critical angle
• B. A ray passing from denser to rarer medium and not able to pass to rarer medium at an angle greater than critical angle
• C. A ray passing from either denser to rarer medium or rarer to denser medium and not able to pass any medium at an angle smaller than critical angle
• D. None of the above