17. Which of the following is not necessarily valid for root-locus pattern? (a) The n finite zeros and m poles are plotted on the s-plane. Then (m – n) indicates the number of non-finite zeros. (b) The number of poles gives the number of loci. (c) A value of s on the real axis is a point on the root locus, if the total number of poles and zeros on the real axis to the right of the point is even. (d) There are as many asymptotes as non-finite zeros.