Consider the following scenarios in a digital marketing context. Match each scenario with the most appropriate CRO use case to enhance user acquisition:
- Scenario I: A website wants to test two different homepage designs to see which one leads to more newsletter sign-ups.
- Scenario II: A SaaS platform aims to understand where users most frequently drop off during the onboarding process.
- Scenario III: An e-commerce store is looking to customize product recommendations based on users' browsing history.
- Scenario IV: A mobile app developer seeks to improve the app’s interface based on direct user feedback on its latest feature.
Identify the correct CRO use case for each scenario.