The passage “universe of mystery and a treasure house of beauty” means

The phrase describes the universe itself. It calls the world a place full of mystery and a store of beauty, and that is exactly what option B says. In comprehension questions like this, the safest method is to check what the quoted words literally describe before reading the passage's broader moral into them.

Why the others fall short:

• A talks about helping a person develop his best qualities. That is a general aim of education, not what the phrase describes.
• C claims education makes a man wise and beautiful. The phrase says nothing about the effect of education on a person's character.
• D claims education makes a man bounteous and large-hearted. Again, this is a claim about the learner, not about the universe.

The core skill here is metaphor-reading in passage comprehension: separate the image from the lesson the author draws from it. The idea that the world is a site of wonder that rewards curiosity links to the value of learning and aesthetic sensibility, themes that come up in Mains ethics and essay papers.

Trap: aspirants often pick the option that sounds like the passage's moral (C or D) rather than the one that matches the literal meaning of the quoted phrase.