The clamp of is the solution. The strongest resistance black can try is a; b creates too many cutting points, while c alows white to escape.
After black connects, white connects under with and escapes. Although black can try
, he cannot contain white. It leads to a running fight with a couple of variations depending on when black decides to push or hane. However, you should find that in each variation white will escape by capturing when black hanes too early, or will have room for a second eye when black hanes too late.