Here we see that Jesus is speaking to the Religious People of Israel. The Leaders and those who called themselves committed to God.
In the Passage directly Before (Vs. 27-33) We see them challenging Jesus and His Heavenly Authority. Read Mark 11:28 “28 and they said to him, “By what authority are you doing these things, or who gave you this authority to do them?”
Jesus does as He normally does, He replies to their question with a question. And when they can’t answer, He tells a story (Parable)