If a string value is put in both a cache and a key value map (KVM) using the same key, which one is true?

If a string value is put in both a cache and a key value map (KVM) using the same key, which one is true?
A . The object will expire from both locations after the TimeToLive has passed.
B . The object will be stored in Cassandra twice
C . When object is retrieved from KVM, the object with the same key will be returned from the cache instead to improve performance
D . One of the inserts (either to cache or to KVM) will fail as you cant insert the same key twice

Answer: A