Explanation
This is not a permissions issue so you do not need to assign the Security Reader role.
The on-premises Active Directory domain is named contoso.com. User2 could sign on as [email protected] but you would first need to change the UPN of User2 to [email protected].

Explanation:

B: Overview of Microsoft Defender for Endpoint Plan 1, Reporting
The Microsoft 365 Defender portal (https://security.microsoft.com) provides easy access to information about detected threats and actions to address those threats.
The Home page includes cards to show at a glance which users or devices are at risk, how many threats were detected, and what alerts/incidents were created.
The Incidents & alerts section lists any incidents that were created as a result of triggered alerts. Alerts and incidents are generated as threats are detected across devices.
The Action center lists remediation actions that were taken. For example, if a file is sent to quarantine, or a URL is blocked, each action is listed in the Action center on the History tab.
The Reports section includes reports that show threats detected and their status.
E: What can you expect from Microsoft Defender for Endpoint P1?
Microsoft Defender for Endpoint P1 is focused on prevention/EPP including:
Next-generation antimalware that is cloud-based with built-in AI that helps to stop ransomware, known and unknown malware, and other threats in their tracks.
(E) Attack surface reduction capabilities that harden the device, prevent zero days, and offer granular control over access and behaviors on the endpoint.
Device based conditional access that offers an additional layer of data protection and breach prevention and enables a Zero Trust approach.
The below table offers a comparison of capabilities are offered in Plan 1 versus Plan 2.

Incorrect:
Not A: P2 is by far the best fit for enterprises that need an EDR solution including automated investigation and remediation tools, advanced threat prevention and threat and vulnerability management (TVM), and hunting capabilities.
Reference:
https://learn.microsoft.com/en-us/microsoft-365/security/defender-endpoint/defender-endpoint-plan-1
https://techcommunity.microsoft.com/t5/microsoft-defender-for-endpoint/microsoft-defender-for-endpoint-plan-1-now-included-in-m365-e3/ba-p/3060639

Explanation

https://docs.microsoft.com/en-us/mem/intune/enrollment/enrollment-restrictions-set#change-enrollment-restrictio

View email security reports in the Microsoft 365 Defender portal
The aggregate view shows data for the last 90 days and the detail view shows data for the last 30 days Reference:
https://learn.microsoft.com/en-us/microsoft-365/security/office-365-security/reports-email-security