J.R. S. answered 05/06/20
Ph.D. University Professor with 10+ years Tutoring Experience
The "most" products is a poor descriptor for whoever wrote the question. They all produce the same number of products, i.e 1 product. The question is probably asking which reaction proceeds further to the products. You can rank them by comparing the values of Kc from the largest value to the smallest value.
C > A > D > B