Which Statement Below Best Explains What Is Meant by the Statement

Which statement below best explains what is meant by the statement, "An organocuprate reaction with a vinyl halide is stereospecific"?

A) The reaction of a specific stereoisomer with the R₂CuLi reagent will yield that particular stereoisomer as the product.
B) The reaction of a vinyl halide with the R₂CuLi reagent will only yield the cis product.
C) The reaction of a vinyl halide with the R₂CuLi reagent will only yield the trans product.
D) The reaction of a vinyl halide with the R₂CuLi reagent will only yield one enantiomer product-either R or S configuration.