Which of following is/are trend (s) in ecological succession? (i) An increase in complexity of species. (ii) An increase in productivity. (iii) An increase in community stability and species diversity. (iv) A decrease in nonliving organic materials.

• A. (i) and (iii)
• B. (i) and (iv)
• C. (i), (ii) and (iii)
• D. (i), (ii), (iii) and (iv)