Which is not a way to manipulate an independent variable?

Which is not a way to manipulate an independent variable? (a) Presence Technique

(b) Amount technique

(c) Type technique

(d) Random technique

✅ Correct option: (d) Random technique

Explanation:

Independent variables are manipulated through presence/absence, amount, or type. Random technique refers to assignment of participants, not manipulation of variables. Randomization controls bias but does not manipulate the independent variable itself.

10 Related PPSC Facts:

Independent variables are manipulated. Presence technique uses treatment vs no treatment. Amount varies intensity. Type varies kind of treatment. Randomization assigns participants. Manipulation precedes measurement. Control groups receive no treatment. Experimental design requires manipulation. Random assignment improves internal validity. Manipulation distinguishes experiments from surveys.