The correct option is HYPOTHESIS.
An hypothesis refers to an explanation, that is proposed and which is temporarily accepted in order to investigate an observed phenomenon. Sometimes it is described as educated guess.
Scientific hypothesis is the first step that is always taken by scientists during the course of scientific investigation and it serves as the basis on which the scientific investigation is based. A hypothesis must be testable and the explanation offered abut it must be based on prior scientific knowledge.
The answer is A, as the protein does not have any affect of the movement of the cologne.
