Validity of an experiment is based upon: a. performing a fair test, in which only the dependent variable affects the independent variable. b. using multiple independent variables. c. using a control group. d. performing a fair test in which only the independent variable affects the dependent variable.

D. Performing a fair test in which only the independent variable affects the dependent variable.

Explanation:

Validity is a measure of how correct the result of the experiment is. The validity of the experiment is based upon the correctness of the research topic, and correctness and implementation of the scientific procedures.  

Performing a fair test that can be based upon use of the independent and dependent variables can yield results which will be valid and acceptable. The independent variable in an experiment is the variable which can be changed to know it's affect on the dependent variable. The dependent variable will help in determining the result of the experiment.

the moon affects the earth gravitation ally, causing certain motions of that body and also producing tides in its ocean and atmosphere. the tidal wave in our atmosphere is, however, far too minute to be an effective cause in any known meteorological phenomenon.

explanation:

the five characteristics of adolescence are biological growth and development, and undefined status, increased decision making, increased pressure and the search of self.