Which of the following ciphers is known for being unbreakable?

Which of the following ciphers is known for being unbreakable?

• One-time pad
• RSA
• WPA
• 3DES 

EXPLANATION

One-time pads (OTP) are unbreakable under the following conditions: the pad is at least as long as the encoded message, is randomly generated, and is used only once. Due to these constraints, as well as the need to share the key ahead of time, their practicality has been limited.

SOURCE

https://crypto.stackexchange.com/questions/20748/proving-the-semantic-security-of-the-one-time-pad