Consider the following statements regarding root loci:

• A. all root loci start from the respective poles of g(s) h(s)
• B. all root loci end at the respective zeros of g(s) h(s) or go to infinity
• C. the root loci are symmetrical about the imaginary axis of the s-plane
• D. all root loci start and end from the respective poles of g(s) h(s) or go to infinity