Annika has difficulty forming long-term memories of classroom lessons because she can't focus her attention long enough to mentally grasp what is being taught. Annika most clearly demonstrates difficulty withA)echoic memory. B)iconic memory. C)encoding. D)retrieval.

C)encoding.                      

Explanation:

Encoding: In psychology, encoding is also referred to as memory encoding and is described as one of the three distinct stages in a person's memory process. In the process of forming new memories, and individual's brain should encode or process a different piece of new information or facts into a "storable form" in order to retrieve or recall that particular information at a later time whenever necessary for him or her.

An individual generally encodes different information via three important areas including semantic encoding, visual encoding, and acoustic encoding.

In reference to the given question, Annika most clearly demonstrates difficulty with encoding.