During a lightning storm, what is a major risk for large trees?

The major risk for large trees during a lightning storm arises from people seeking refuge under them. When a thunderstorm occurs, individuals may instinctively look for shelter from the rain or storm conditions, and large trees might seem like a safe option due to their size and coverage. However, this poses a significant danger, as tall trees are more likely to be struck by lightning. Lightning typically strikes the tallest object in an area, and being under a tree when it is struck can have fatal consequences due to the electrical discharge traveling down the tree and potentially through the ground.

The other choices do not adequately address the primary risk associated with trees during a lightning storm. While animals may be attracted to trees, this is a minor concern compared to the danger to humans. Similarly, weak root systems might affect a tree's stability in high winds, but it is not a direct risk during a lightning strike. The blocking of visibility is also less relevant when considering the immediate dangers presented during a lightning event.