In the levels of processing model of memory, information that gets processed at a (such as accessing the meaning of a word or phrase) is more likely to be retained longer and form a stronger memory than information that is processed at a level (such as the visual characteristics of a word).
a) deeper; shallower
b) shallower; deeper
c) higher; lower
d) lower; higher

Deeper, shallower

Explanation:

The level of processing model describes that deeper processing related to better memory and shallow processing is related to the poorer memory. The level of processing model was given by Craik and Lock hart in 1972. It was related to the processing of memory, as much as the processing occurs deeper, the long memory trace will found.  

This model has two types of processing in memory:

The deep processing:

The shallow processing:

depends.

explanation: