What should an accumulator variable be set to before it is used to accumulate a total?

Virtual Time Disks are physical disks mapped through Hyper-V and granted exclusively for use with guest VMs

Indicate whether the statement is true or false

The __________ attack is where the attacker chooses a list of messages before attempting to break the user's signature scheme, independent of the user's public key. The attacker then obtains from the user valid signatures for the chosen messages.

Fill in the blank(s) with the appropriate word(s).