Which Statement Best Describes the Relationship Between Walking Early and Later

Which statement best describes the relationship between walking early and later intelligence test scores?

A) There is no relationship between the two abilities.
B) Positive,as kids who walk early tend to score higher on intelligence tests.
C) Negative,as kids who walk early do more poorly on intelligence tests.
D) Unclear,as it all depends on whether a child crawls before he or she walks.