Which single Security Blade can be turned on to block both malicious files from being...

 Anti-Virus is the single Security Blade that can be turned on to block both malicious files from being downloaded as well as block websites known to host malware. Anti-Virus scans files and email attachments for viruses, worms, trojans, and other types of malware. It also uses ThreatCloud, a collaborative network that delivers real-time dynamic security intelligence, to detect unknown malware based on their behavior3. Anti-Bot is a Security Blade that detects and blocks botnet communications, but it does not scan files or block websites. URL Filtering is a Security Blade that enables administrators to control access to web applications, but it does not scan files or detect malware.