A cleaning company uses $10 of chemicals, $30 of labour, and $5 of miscellaneous expenses for each house it cleans. After some quality complaints, the company has decided to increase its service quality which causes chemicals expenses to increase by 50%. Multifactor productivity is multiplied by:

A) 0.10

B) 0.50

C) 0.91

D) 1.50

E) None of the above