HELLO LAKSHAY,
the answer is obswervable characteristics of existing organisms,,because,,
organisms are classified into hierarcjies of similarity and based solely on morphology and other two options are eliminated completely for this reason
and other reason is.........
it is compared and categorized the things under the overall similarity of apperance
and also........
it classify the organisms based on overall similarity and morphology or other observable traits,regardless of thier phylogeny ,or evolutionary relation
It is closely related to numerical taxonomy which is concerned with the use of numerical methods for taxonomic classification
so option C is the correct answer
THANK YOU
