When requiring certificates for mobile devices, the authentication method should be set to one of the following:
Username and Password
RADIUS
SecurID (RSA SecurID)
So, the correct answer is option B, "SecurID."
Options A, C, and D are not standard authentication methods for mobile devices in this context.

Authentication rules are defined for user groups, not individual users or all users in the database. Authentication rules allow you to control which user groups can access specific resources or services through the Security Gateway. You can define different authentication methods and schemes for different user groups, such as Check Point Password, OS Password, RADIUS, TACACS, SecurID, LDAP, or Certificate. You can also define different session timeouts and source restrictions for different user groups. Authentication rules are processed before the network access rules in the rule base.

The biggest benefit of policy layers is that they enable flexible control over the security policy. Policy layers and sub-policies allow administrators to break one policy into several virtual policies, each with its own set of rules and actions. Policy layers can be ordered, shared, and reused across different policies. Policy layers can also include Threat Prevention as a sub-policy for the firewall policy. Reference: [Check Point R81 Security Management Guide]

According to the Check Point R81 training course, the Proxy ARP feature for Manual NAT in R81.20 requires the configuration of the local.arp file on the Security Gateway. This file contains the mapping of IP addresses to MAC addresses for NATed hosts. The other options are either incorrect or irrelevant. Reference: Certified Security Expert (CCSE) R81.20 Course Overview

The Check Point software blade that provides protection from zero-day and undiscovered threats is Threat Emulation. Threat Emulation is a sandboxing technology that inspects files for malicious behavior in a virtual environment before they reach the end user. Threat Emulation can detect and block malware that tries to evade traditional signature-based solutions by using unknown or obfuscated techniques. Threat Emulation can also generate forensic reports and provide actionable intelligence on the malware origin and behavior.