What is the meaning of the following traffic sign?

1. Tunnel entrance.
2. Barrier ahead.
3. Correct answer: Vehicle height restriction. No entry for a vehicle that exceeds, with its cargo, the height that is indicated in the sign.
4. Narrow and low roadway.

WhyThe sign limits height: if the vehicle with its cargo is higher than shown, you may not enter. It is not a tunnel or a barrier.