Explanation
Based on Subscriber Preview List or Data Extension is a Preview & Test Content Personalization option that allows marketers to preview how an email will look for different subscribers based on their personalization attributes and dynamic content rules. Marketers can select a list or data extension that contains the subscribers they want to preview, and then use the arrows or search function to navigate through the different previews.

Explanation
Einstein Copy Insights is the tool that should supply insights into the tone of subject lines. Einstein Copy Insights is a feature that uses natural language processing and machine learning to analyze your subject lines and provide suggestions for improvement. It also shows you the tone of your subject lines, such as positive, negative, neutral, or mixed, and how it affects your engagement metrics, such as open rate, click rate, etc.
Einstein Recommendations is a feature that uses artificial intelligence to provide personalized product or content recommendations for your subscribers based on their behavior and preferences. Einstein Messaging Insights is a feature that uses predictive intelligence to identify issues or opportunities with your email campaigns based on performance trends and anomalies.

Explanation
Einstein Engagement Scoring is the correct answer. This tool allows you to use artificial intelligence to score your subscribers based on their engagement behavior, such as opens, clicks, conversions, etc. You can use Einstein Engagement Scoring to easily target your most loyal subscribers by filtering them based on their predicted engagement level or score. You can also use Einstein Engagement Scoring to segment your subscribers based on their predicted attrition risk or optimal send time. Google Analytics Audience is not a valid option, as this tool only allows you to measure and analyze web traffic and behavior, not email engagement. Path Optimizer is not a valid option either, as this tool only allows you to test different paths or content variations in a journey based on different engagement metrics, not target loyal subscribers. You can learn more about this in the [Einstein for Marketing Cloud] module on Trailhead.

Explanation
Using Automation Studio to query a population into a data extension is the optimal segmentation process that NTO should use to ensure only Platinum members receive the journey emails. This will reduce the size of the data extension and improve the performance of the journey. Using Filter Contacts criteria or a Decision Split activity will still load all loyalty members into the journey, which is inefficient and unnecessary. [Source:
Trailhead]

Explanation
Engagement Split is the Journey Builder activity that NTO should use. Engagement Split is an activity that allows you to split contacts based on how they interacted with a previous email send, such as opened, clicked, or converted. You can use this activity to include specific content for your most engaged customers and different content for your least engaged customers. Frequency Split is an activity that allows you to split contacts based on how often they have received messages from your account. Scoring Split is an activity that allows you to split contacts based on their Einstein Engagement Score.