If Grass Stores 1,000 Energy Units Received from the Sun,the $\rightarrow$

Multiple Choice

If grass stores 1,000 energy units received from the sun,the ecological efficiency of the ecosystem is 10%,and the trophic levels are grass $\rightarrow$ cow $\rightarrow$ human,how many units of energy does the human receive of the original 1,000 units?

A) 900
B) 200
C) 100
D) 10
E) 1