Explanation

Box 1: Yes
Most services go to private preview then public preview before being released to general availability.
The private preview is only available to certain Azure customers for evaluation purposes. The public preview is available to all Azure customers.
Box 2: No
Azure services in public preview can be managed using the regular management tools: Azure Portal, Azure CLI and PowerShell.
Box 3: No
Services in private or public preview are usually offered at reduced costs. However, the costs increase, not decrease when the services are released to general availability.

Section: Understand Security, Privacy, Compliance and Trust
Explanation:
Azure Key Vault is a secure store for storage various types of sensitive information including passwords and certificates.
Azure Key Vault can be used to Securely store and tightly control access to tokens, passwords, certificates, API keys, and other secrets.
Secrets and keys are safeguarded by Azure, using industry-standard algorithms, key lengths, and hardware security modules (HSMs). The HSMs used are Federal Information Processing Standards (FIPS) 140-2 Level
2 validated.
Access to a key vault requires proper authentication and authorization before a caller (user or application) can get access. Authentication establishes the identity of the caller, while authorization determines the operations that they are allowed to perform.
References:
https://docs.microsoft.com/en-us/azure/key-vault/key-vault-overview

Section: Describe identity, governance, privacy, and compliance features Explanation:
Azure Information Protection can encrypt documents and emails.
Azure Information Protection is a cloud-based solution that helps an organization to classify and optionally, protect its documents and emails by applying labels. Labels can be applied automatically by administrators who define rules and conditions, manually by users, or a combination where users are given recommendations.
The protection technology uses Azure Rights Management (often abbreviated to Azure RMS). This technology is integrated with other Microsoft cloud services and applications, such as Office 365 and Azure Active Directory.
This protection technology uses encryption, identity, and authorization policies. Similarly to the labels that are applied, protection that is applied by using Rights Management stays with the documents and emails, independently of the location - inside or outside your organization, networks, file servers, and applications.
References:
https://docs.microsoft.com/en-us/azure/information-protection/what-is-information-protection
https://docs.microsoft.com/en-us/azure/information-protection/quickstart-label-dnf-protectedemail

Section: Understand Azure Pricing and Support
Explanation:
Preview features are made available to you on the condition that you accept additional terms which supplement the regular Azure terms. The supplemental terms state:
"PREVIEWS ARE PROVIDED "AS-IS," "WITH ALL FAULTS," AND "AS AVAILABLE," AND ARE EXCLUDED FROM THE SERVICE LEVEL AGREEMENTS AND LIMITED WARRANTY." References:
https://azure.microsoft.com/en-gb/support/legal/preview-supplemental-terms/