To classify an organism a scientist finds in the field, which of these will the scientist first compare to other known organisms?
a. dietary habits
b. ecological niche
c. physical structure
d. reproductive method

The answer is C. Physical structure.

Different species can share dietary habits, ecological niches, and reproductive method although they are not related. So, classifying organisms based on these features is not helpful a lot. It is known that different species differ in DNA sequence. Since physical structures are determined by DNA sequences, physical structures could show in first sight difference between species. Therefore, to classify organism found in the field, the scientist will start from comparing its physical structures to the other known organisms.

1. true.2. true.3. true.4. false.5. true.the concept of darwin's theory of evolution involves the idea that there are limited resources in a given living environment and that the organisms which live within have variations in their genetic make up due to random mating. the ones with beneficial genetic variations can express certain traits which give them an upper hand in surviving and reproducing in the said environment compared to ones who may have a more disadvantageous variation in traits. over time, the organisms with an upper hand will survive and reproduce more frequently and pass on their beneficial genes while the others die. the result is evolution, where we observe (usually, but not always) eventually, phenotypic distinct changes.