Explanation
To share report folders with different groups of users with different levels of access, an administrator can use folder sharing settings under setup. Folder sharing settings allow administrators to share report folders with public groups, roles, roles and subordinates, territories, or portal roles with view or edit access. In this case, the administrator can share the Helpdesk folder with Support Agents with view access so they can run Helpdesk reports but not edit them; and share the R&D folder with Support Managers with edit access so they can view and edit R&D reports. References:
https://help.salesforce.com/s/articleView?id=sf.reports_builder_folders_sharing.htm&type=5

Explanation
To provide appropriate access to a report that contains shoe records for all of the sales reps on their team, the administrator should configure three items:
A custom report type that includes the shoe object and its fields
A folder access that grants access to the sales manager and their team members to view and run reports in that folder A field level security that allows the sales manager and their team members to see all the fields on the shoe object Report subscription, while useful for scheduling and delivering reports, does not affect access to the report itself. References:
https://help.salesforce.com/s/articleView?id=sf.reports_builder_create_report_type.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.reports_manage_folders.htm&type=5
https://help.salesforce.com/s/articleView?id=sf.admin_fls.htm&type=5

Explanation
Multi factor authentication (MFA) is a security feature that requires users to verify their identity using two or more factors when they log in to Salesforce. It can help prevent unauthorized access to Salesforce byadding an extra layer of protection beyond username and password. Enabling MFA can be done by administrators in the security settings or by users in their personal settings. Disabling TLS requirements for sessions, customizing organization wide defaults, or enabling caching and autocomplete on login page are not actions that would prevent unauthorized access to Salesforce; in fact, they may reduce security or have no effect on security at all.
References:https://help.salesforce.com/s/articleView?id=sf.security_mfa.htm&type=5

Dashboards show data from source reports as visual components that provide a snapshot of key metrics and performance indicators. Dashboards need to be refreshed manually or scheduled to run on a regular basis to reflect the most recent data from the reports. The running user of a dashboard determines whose security settings are applied when the dashboard is run. If the running user is different from the viewer of the dashboard, they may see different data based on their permissions and sharing settings.
References:https://trailhead.salesforce.com/en/content/learn/modules/lex_implementation_dashboards_and_repo