Suggest Appropriate Chart Types

Recommend the most appropriate Excel chart type(s) to visualize the following data and insight: 
Data Description: [e.g., Monthly website traffic over the last 2 years, Budget allocation across different departments, Correlation between study hours and exam scores, Market share comparison of 5 competitors]. 
Key Insight/Message: [e.g., Show the upward trend in traffic, Compare department spending clearly, Illustrate the positive relationship, Show relative size of competitors]. 
Explain why the suggested chart type(s) (e.g., Line, Bar, Pie, Scatter) are suitable.