Which of the Following Was Achieved by Baddely's Concept of Working

Which of the following was achieved by Baddely's concept of working memory?

A) It expands the functions and processes of short-term memory.
B) It expands the functions and processes of long-term memory.
C) It integrates sensory memory, short-term memory, and long-term memory into a single, complex system.
D) It takes the place of the old concept of sensory memory.