Correct Answer: High and mighty

Solution : The correct choice is the third option.

Explanation: "High and mighty" is an idiom used to characterise individuals who are arrogant, self-important, or condescending. It aligns with the idea of pride and a lack of humility, making it a suitable choice in this context.

So, the correct sentence would be: "The high and mighty forget the fact that the world is tangible."

The meanings of the other options are as follows:

1. Hobson’s choice: This idiom refers to a situation in which someone is left with no real choice or alternative.
2. Head and shoulders: This idiom typically refers to someone or something being significantly better or outstanding in comparison to others.
3. Hard-nosed attitude: This idiom describes a tough, practical, or uncompromising attitude.