If the uncatalyzed reaction occurs in a single elementary step, why is it a slow reaction?

The choices can be found elsewhere and as follows:

A)The reaction requires the collision of three particles with the correct energy and orientation. 
B) All reactions that occur in one step are slow. 
C)The probability of an effective three-particle collision is low. 
D) The transition state is low in energy.

I think the correct answer from the choices listed above is option C. If the uncatalyzed reaction occurs in a single elementary step, it is a slow reaction because the probability of an effective three-particle collision is low.

Mass is the amount of matter in an object.  weight is the measurement of the pull of gravity on an object.  say for example, you travel to the moon which has a different gravitational field compared to the gravitational field of earth. (gravitational fields: earth = 1, moon = 0.165)  now when you are on the moon, the pull of gravity on you is different than on the earth. and as weight is the measurement of the pull of gravity on an object, that means yes, your weight can and will change on the moon.  however, on the moon, on earth or even on jupiter, the amount of mass inside of you remains the same. meaning your physical mass remains constant.  in conclusion it is possible for your weight to change as your mass remains constant. 

What is the gold assay