49.Which of the following statements about energy flow is incorrect? 
(A)Only net primary productivity is available to consumers.
(B)Only about one-thousandth of the chemical energy fixed by photosynthesis reaches a tertiary-level consumer.
(C)Secondary productivity declines with each trophic level.
(D)About 90% of the energy at one trophic level does not appear at the next.
(E)Eating meat is probably the most economical way of acquiring the energy of photosynthetic productivity.