If the battery of our vehicle is one of the so-called "maintenance-free" batteries, we should...
A)Refill it periodically with distilled water.
B)Check that the terminals are clean and well tightened.Correct
In a so-called "maintenance-free" battery we do not need to worry about the electrolyte, that is, the mixture of distilled water and sulfuric acid. We will only need to pay attention to the fastening of the terminals so that they are well tightened, clean and covered with grease.