In marketing research, sampling refers to A. testing the effectiveness of a marketing alternative in a supervised setting. B. the collection of various secondary data through electronic or mechanical means. C. allowing a subject to experience firsthand a new or updated product or service. D. selecting representative elements from a population and treating their answers as typical of all those in whom they are interested. E. testing members from all ages, both genders, and different levels of income and education to guarantee reliable information.

D. selecting representative elements from a population and treating their answers as typical of all those in whom they are interested.

Explanation:

Marketing comprises of all the activities such as, identifying, anticipating set of medium and processes for creating, promoting, delivering, and exchanging goods and services that has value for customers. It basically, involves understanding customer needs, building and maintaining healthy relationships with them in order to scale up your business.

In marketing research, sampling refers to selecting representative elements from a population and treating their answers as typical of all those in whom they are interested.

ans.

heterothermic organisms include those organisms that can switch between homeothermic (having body temperature higher than environment) and poikilothermic (having variation in internal body temperature) strategies.

some migratory birds show heterothermy as they decrease their metabolic rate during cold nights to keep their body temperature low. drop in metabolic rate allows increase in production efficiency of birds that reduces the internal body temperature to make it equal to external cold temperature during cold nights.

thus, the correct answer is 'birds allow their temperature drop in order to increase their production efficiency.'