Answer:
C. Forming the activated complex requires energy,
Step-by-step explanation:
For any reaction (whether exothermic or endothermic) the reactant molecules need some minimum amount of energy known as Threshold energy.
Reactant molecules have some internal energy and they require some extra amount of energy to reach the threshold energy which is known as activation energy.
This activation energy is required to from an activated complex.
The activated complex is formed where reactant molecules come closer to each other and undergo effective collision. This causes the formation of products.