The 3-domain system of classification of all living organisms is based on analysis of
a. morphological traits
b. nuclear and ribosomal dna, along with morphological triats
c. nuclear dna
d. ribosomal rna
e. mitochondrial dna

The correct answer is option d. "ribosomal RNA".

Explanation:

Ribosomal RNA, is the main component of the ribosome and is essential for protein synthesis in all living organisms. Ribosomal RNA has proved to be the most reliable molecule to establish evolutionary relationships among species. The study of the variations in rRNA sequences allowed the establishment of the 3-domain system of classification of all living organisms: Eukaryotes, Bacteria, and Archaea.

it would be c. xylem.

if you add everything up correctly you should get 69 i got this because 50 plus 19 is it