The diagram represents a food pyramid. The concentration of the pesticide DDT in individual organisms at level D is higher than the concentration in individuals at level A because DDT is
A. produced by organisms at level C ingested by
those in level D
B. passed through levels A, B, and C to organisms
at level D.
C. excreted by organisms at level A as a toxic
waste.
D. synthesized by organisms at level D.

The answer is "Choice b".

Explanation:

In the given question diagram is missing. so first, we define the diagram after that we explain why the above given choice is correct.  

In the attached file the food pyramid can be a divide into the level, in which the D pesticides use the "dichloro-diphenyl-trichloroethane ", which concentration is higher than its entities from the level of A because DDT is transferred with species at level D by levels A, B, and C, that's why the choice "b" is correct.  

a. the production of carbon dioxide through the process of photosynthesis

is this a psat question, if so do not cheat try your best.