Which of these is an optional feature，requiring the purchase of a separate license after 30 days？（）

单项选择题WhichoftheseisadrawbackinusingMcAfeeheuristicscanning？（）

A. heuristic scanning cannot detect new malware with an unknown signature
B. heuristic scanning requires a separate license key
C. heuristic scanning increases the probability of false positives
D. heuristic scanning increases the probability of false negatives

单项选择题WhendoyouneedtoconfiguretheP1interface？（）

A. whenever you have an upstream proxy
B. whenever you intend to deploy the L4TM in blocking mode
C. whenever you want to enable the WSA proxy
D. whenever you have a separate management VLAN orsubnetwork

单项选择题WhichoftheseuserICAP？（）

A. anti-malware scanning
B. data loss prevention polices
C. decryption policies
D. CiscoIronPort Data Security policies

单项选择题WhichfilecharacteristiccannotbeusedintheCiscoIronPortDataSecuritypolicies？（）

A. file type
B. file size
C. file age
D. file  name

单项选择题Whichstatementisfalse？（）

A. custom URL categories cannot contain IP addresses
B. custom URL categories cannot override predefined URL categories
C. custom URL categories can contain domain names
D. custom URL categories can use regular expressions