小緹是「極西地帶進口」公司的行銷人。這家公司打算推出新的智慧型手機應用程式協助客戶更輕鬆訂購產品，小緹就是這項專案的負責人。多虧 Google 提供的建議，開發團隊已整合多種功能來提升轉換數據。在行銷部門副總裁的堅持下，你必須評估購物車和結帳功能的成效。 該團隊可透過哪一項 Google 服務測試應用程式的使用者介面與功能？

Firebase A/B Testing is the correct choice because it allows developers and marketers to run experiments on their app's user interface and features to determine which variations perform best. This directly addresses the need to evaluate the effectiveness of the shopping cart and checkout functions. Optimizely and SplitMetrics are third-party A/B testing tools, but Firebase is Google's integrated solution for app development and testing. Google Analytics 360 is primarily for advanced analytics and reporting, not for directly conducting A/B tests on app features.