Answer:
A
Step-by-step explanation:
This is why for a chemical reaction to occur (that doesn’t occur spontaneously), the molecules need to be excited (put on a higher energy state) so the reactants can form new bonds and form products. This minimum energy required to excite the atoms is called activation energy.
The activation energy excites the reactant molecules such that their bonds are distorted hence assuming an unstable form, called transition state. Because of the instability of the excited reactants, their bonds are easily broken to form new ones as the reaction proceeds to form products.