In your own words, describe the base-pairing rules in any DNA molecule (Hint: Think about the BFF's)​

There are four different bases, each of which pairs with only another. Adenine (A) pairs with Thymine (T), and Guanine (G) pairs with Cytosine (C). This rule is universal to all DNA. A good way to remember is apples in the tree (adenine and thymine), cars in the garage (cytosine and guanine) (credit to the Amoeba Sisters)

the answer is; comparing the frequency of collisions with and without the device

this makes the anti-collision system an independent variable and the collisions a dependent variable. if there are fewer collisions with an anti-collision system that without, then it can be stated that the system is a success. essentially, collisions under an anti-collision system are compared with the frequency of collisions by cars with the human drivers.