Lightning and thunder occur when an electric field is generated between the cloud and the earth. When there are opposite charges, electricity travels through them and generates what we visually see as lightning and auditory we hear as thunder.
For the particular case of the meadow, there is not only direct conduction between the floor (which is full of water) and the sky, but also an individual is the only 'tall' object that can reach thunder more easily.
In the case of the tree, although it is taller, it is vulnerable to thunder falling there and it can fall on the person or be injured.
The tower is made of metal, which is a direct conductor of electricity that will expose the person in contact with it.
The wood construction might be ideal, but the floor could be damp, and remember that water is a conductor of electricity that could bring us electricity.
The car acts as an insulator for its tires and also serves as a capsule. It cuts the flow between heaven and earth which would allow it to serve as a good refuge.
Therefore the correct answer is B.
