Regardless of the Research Methodology Being Used, Researchers Studying Changes

Regardless of the research methodology being used, researchers studying changes in intelligence over the lifespan usually find that:

A) fluid intelligence appears to decline somewhat earlier than crystallized intelligence does.
B) crystallized intelligence appears to decline somewhat earlier than fluid intelligence does.
C) both fluid and crystallized intelligence show similar declines in late adulthood.
D) both fluid and crystallized intelligence show similar declines in middle adulthood.