Answer: B
73) A porcupine eats 3,000 J of plant material. Of this, 2,100 J is indigestible and is eliminated as feces, 800 J are used in cellular respiration, and 100 J are used for growth and reproduction. What is the approximate production efficiency of this animal?
A) 0.03%
B) 3%
C) 10%
D) 27%
E) 33%