In the production process of traditional mature vinegar, there are

Using the constant solute mass before and after the change to solve the problem.

Let the mass of 3% semi-mature vinegar be x.

X×3% = 500 5.4%

The solution is x = 900 g.

Therefore, the total mass of fished ice and evaporated water = 900g-500g = 400g.

So choose B.