What does the tRNA (truck) molecule pick up AND where does it bring it?

Explanation:

tRNAs pick up specific amino acids, transfer those amino acids to the ribosomes, and insert them in their proper place according to the mRNA genetic "message.

tRNA take amino acid from: Messenger RNA (mRNA) molecules carry the coding sequences for protein synthesis and are called transcripts; ribosomal RNA (rRNA) molecules form the core of a cell's ribosomes (the structures in which protein synthesis takes place); and transfer RNA (tRNA) molecules carry amino acids to the ribosomes during protei

well, that's easy; the answer's c, "it reduces contamination of the water and substrate of the estuary."