What Was the Outcome of the Process/product Debate During the 1970s

What was the outcome of the process/product debate during the 1970s?

A) Perceptual abilities were the focus of instruction for students with learning disabilities.
B) Both perceptual and product approaches were found to be effective for teaching students with learning disabilities.
C) Brain injury was determined to be the cause of learning disabilities.
D) Explicit instruction was determined to improve student's academic skills.