Azure Data Factory (ADF) is made up of 4 core components. These components work in collaboration to provide a platform that allows composing data-driven workflows with steps to move & transform data. 
Which component can be described by: 
“It is created to perform a specific task by composing the different activities in the task in a single workflow. This can be scheduled to execute, or a trigger can be defined that determines when an execution needs to be kicked off.” 
 

Answer options:

A.Activity
B.Pipeline
C.Dataset
D.Linked Service
E.None of these

Correct Answer: B 
An Azure subscription can consist of 1 or more Azure Data Factory (ADF) instances. ADF is composed of 4 core components i.e Dataset, Activity, pipeline and Linked Services. These components work in collaboration to provide a platform where data-driven workflows can be composed with steps to move & transform data. 

Option A is incorrect. Activity is a specific action executed on the data in a pipeline like the ingestion or transformation of the data. Each pipeline may consist of 1 or more activities in it.
Option B is correct. The given description is for Pipeline.
Option C is incorrect. This is the data collected by users which are utilized as input for the ETL process. Datasets can be in various formats like CSV, JSON, text or ORC format.
Option D is incorrect. Linked Service is not the right answer.
Option E is incorrect. The given description is for Pipeline.
Reference: 
To know more about Azure Data Factory, please visit the below-given link: 

https://www.educba.com/azure-data-factory/