Answer:
B. Children who watch a lot of cartoons are more likely to behave badly.
This thesis statement directly addresses Lina's topic of interest - cartoon violence and its impact on children. It takes a clear stance on the issue and presents a specific argument that Lina can develop in her essay. Additionally, it is a debatable statement that invites further discussion and exploration of the topic.
The other options, A, C, and D, are not directly related to Lina's topic of interest or do not present a clear argument for her to develop in her essay.