Final answer:
An understanding of the trends of the periodic table led to the predictions about the behavior and structure of livermorium (Lv).
Step-by-step explanation:
The predictions about the behavior and structure of livermorium (Lv) were most likely led by an understanding of the trends of the periodic table. The periodic table allows scientists to make predictions about the properties and behavior of elements based on their position in the table. By knowing which group an element is in, scientists can determine the number of reactive electrons and make informed predictions about how that element will behave.