What Does the Encoding Specificity Principle State

What does the encoding specificity principle state

A)  Forgetting is due only to the passage of time and will happen to all types of memories. 
B)  Forgetting is often due to a mismatch between retrieval cues and the memory code. 
C)  Forgetting is usually due to interference from competing memories. 
D)  Forgetting often involves purposeful suppression of memories.