Answer:
B. tests the functioning of the system as a whole.
Step-by-step explanation:
System testing is an integral part of system development.
Testing is all about ascertaining the functionality of the system to meet the initial functionality designed before.
From the options, the best answer that suite the definition of system testing is:
B. tests the functioning of the system as a whole.
System testing test the functioning of the system as a whole. It check the functionality of individual part and how it relate or inter-operate with other part in the entire system.