The estimation of consumer demand by monitoring actual purchasing and consumption behavior by a sample

1. The estimation of consumer demand by monitoring actual purchasing and consumption behavior by a sample of consumers is called the The correct answer was: b. observational research approach.. observational research approach. 

...................... b. observational research approach.

 b. observational research approach. 

Ans. Option B is the right choice>>>>>>>>>>>

 b. observational research approach.....................................................................

 b. observational research approach.&&&&&&&&&&&&&&&&&&&&77777

a. consumer survey approach.

option b .........................................................................

My answer is option (B) observational research approach. 

B...................................................................................

answer B ______________________________________________