A species of bird enters a desert environment, and is getting its water by pecking into the stems of cacti. Cacti with which of the following characteristics will most likely survive the damage from these birds? A
numerous spines

B
deep roots

C
a long stem

D
numerous branches

answer; /// i believe the correct answer is (reactants);

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.