After enabling strong, reversible 128-bit Advanced Encryption Standard password type-6 encryption
on a Cisco Nexus 7000, which command would convert existing plain or weakly encrypted passwords
to type-6 encrypted passwords?

A.
switch# key config-key ascii

B.
switch(config)# feature password encryption aes

C.
switch# encryption re-encrypt obfuscated

D.
switch# encryption decrypt type6

Explanation:
This command converts existing plain or weakly encrypted passwords to type-6 encrypted
passwords.

http://www.cisco.com/c/en/us/td/docs/switches/datacenter/sw/5_x/nxos/security/configuration/guide/b_Cisco_Nexus_7000_NXOS_Security_Configuration_Guide__Release_5-x/b_Cisco_Nexus_7000_NXOS_Security_Configuration_Guide__Release_5-x_chapter_010101.html