What causes the USDX to rise?

Could you elaborate on the potential factors that drive the US Dollar Index (USDX) upwards? I'm particularly interested in understanding the economic and financial mechanisms that may be in play. Is it primarily due to strong economic growth in the United States? Or perhaps it's a result of rising interest rates, attracting foreign investors? Additionally, could geopolitical tensions or instability in other major economies play a role in strengthening the dollar against other currencies? I'm keen to get a comprehensive overview of the key factors that influence the USDX's upward movement.