Researchers who were studying plant growth raised plants in two separate rooms. one room had taped conversations playing 24 hours a day; the other room was silent. the researchers found that the plants grew better in the room that had the conversations playing. in this study, the type of room (conversation or silence) would be a

the independent variable    

Explanation:

Independent variable: In a psychological or scientific experiment, the independent variable is referred to as the variable that is being manipulated, controlled, or changed during the process of an experiment.

An independent variable is being manipulated by the researcher to see its effect on the dependent variable, and any manipulation to the independent variable leads to create a change in the dependent variable.

In the question above, the study including the type of room (conversation or silence) would be an independent variable.

it´s related to his charming character.

beauty is not everything, although we can joke that girls only care about the physical or material aspect, the truth is that a real woman looks at more important things, besides intelligence and personality, there are other attitudes that make irresistible to men who are 'unattractive'.

for example develop your sense of humor.