The Research on the Relationship Between Metamemory and Children's Memory

The research on the relationship between metamemory and children's memory performance is complicated.However,a general pattern is that

A) children who have a well-developed metamemory tend to use strategies more wisely,but this does not improve their performance.
B) metamemory is relatively easy to measure in young children.
C) metamemory and memory performance are moderately correlated with each other.
D) the correlations between metamemory and memory performance are significant only when we study younger children.