Answer the following question given this paragraph: 

Raising the temperature of a chemical reaction usually results in a higher rate of reaction. When the reactant particles are heated, they move faster and faster. This results in a greater frequency of collisions. A more important effect of the temperature increase is that the collisions occur with a greater force and are thus more likely to surmount the activation energy barrier and go on to form products. Increasing the temperature of a reaction increases the number of effective collisions between reacting particles, so the reaction rate increases.


Q: Higher temperatures increase the rate of reaction in a lot of chemical reactions because they increase the frequency of what interaction between reactant particles?

 Choices:

- electric

- explosions

- waves

- collisions

A:
collisions
