All are DDOS tools.

Explanations: John the Ripper can be used to crack a variety of passwords, but one limitation is that the output doesn't show if the password is upper or lower case. John the Ripper is a very effective password cracker. It can crack passwords for many different types of operating systems. However, one limitation is that the output doesn't show if the password is upper or lower case. BY using NTLMV1, you have implemented an effective countermeasure to password cracking. NTLM Version 2 (NTLMV2) is a good countermeasure to LM password cracking (and therefore a correct answer). To do this, set Windows 9x and NT systems to "send NTLMv2 responses only". SYSKEY is an effective countermeasure. It uses 128 bit encryption on the local copy of the Windows SAM. If a Windows LM password is 7 characters or less, the has will be passed with the following characters: 0xAAD3B435B51404EE Enforcing Windows complex passwords is an effective countermeasure to password cracking. Complex passwords are- greater than 6 characters and have any 3 of the following 4 items: upper case, lower case, special characters, and numbers.

lsof is a command used in many Unix-like systems that is used to report a list of all open files and the processes that opened them. It works in and supports several UNIX flavors.

31402 is the correct answer.