This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Biochemistry
which is false regarding LAC OPERAN MODEL : 
Select and explain. 
A. CAMP-CAP COMPLEX IS A POSTIVE REGULATOR, B. PROMOTER IS A TRANS ACTING FACTOR, C. Y gene = GALACTOSIDE PERMEASE, D. A gene= GALACTOSIDE ACETYLASE
B: PROMOTER IS A TRANS ACTING FACTOR
Answer: B: PROMOTER IS A TRANS ACTING FACTOR 
Explanation: promotor is a cis acting factor in lac model The lac operon * The lactose operon designated as lac operon. * The lac operon codes for enzymes involved in the catabolism (degradation) of lactose. * lactose is the disaccharide which is made up of glucose & galactose. * It is the inducible operon since the presence of lactose induce the operon to switched on. ref : vasudevan 9th ed