What are four key elements of the study of economics?

As such, it is a social science because it deals with the behavior of people as they deal with this basic issue. There are four key elements to this study: description, analysis, explanation, and prediction. Economics deals with the description of economic activity.

description, analysis, explanation, prediction

c. establishing proper sleep hygiene

the correct answer is: b. pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction.  

because involves two organisms (parents) whose genetic material combines, sexual reproduction leads to genetic variation in new generations of offspring. the offspring is an unique organism, with new genome, more protected with the higher ability to adapted. this process is fundamental to evolution.