Option 1: Distort -> means to twist or misrepresent meaning, which is opposite to understanding something clearly.
Option 2: Retain -> means to keep or hold onto something, unrelated to understanding or decoding.
Option 3: Interpret -> means to explain or understand the meaning of something, closely aligned with decoding or making sense of information.
Option 4: Devise -> means to invent or create something, not related to understanding existing information.
Hence, Option 3: Interpret -> "Decipher" means to decode or make sense of something difficult to understand (like a code or unclear text), which is synonymous with interpreting or explaining meaning -> correct