Which of the following cost function is associated with the production function q = F(f, k) = ve + Vk, where f (with price w) denotes labour and k (with price r) denotes capital? wq if wer, a) C(q) =(rqifw >r. b ) C(q) = (w+ r)q. c) C(q) = 2 wrq. d) c(q) = q2 wr/(w+r)