Which of the following accurately describes the binomial nomenclature naming system?
a. the second word indicates the organism's genus classification.
b. the second word is always capitalized.
c. the first word is always lowercase.
d. the first word indicates the organism's genus classification.

The answer is D. The first word indicates the organism's genus classification.

Binomial nomenclature is a formal system of naming species. As the word 'binomial' suggest, a name is composed of two parts. The first word indicates the organism's genus classification, the second word indicates the species within a genus.

The other statements cannot be true because of the following reasons:
B. The second word is always capitalized. - the first word is always capitalized
C. The first word is always lowercase. - the first word is always capitalized
D. The first word indicates the organism's genus classification. - the second word indicates the species within a genus.