Question

In which of these solvents would boric acid, B(OH)3, be most soluble?
1. C6H6
2. H2O
3. C6H14
4. C2H5OH

Answer 1

As boric acid is an inorganic compound so it is always soluble in inorganic solvents
so here only one inorganic solvent is present which is water(H2O)

Answer 2

I would avoid using vaguely defined terms like "inorganic", it's more informative to use categorize them in terms of polarity.