Can you me in science?

which is an example of a competitive relationship?

a.
silverfish protected by army ants as they walk with them in the jungle

b.
ticks feeding off the blood of a moose who is then harmed

c.
husky dogs and humans traveling through arctic climates

d.
lions and elephants needing a watering hole

D. Lions and elephants needing a watering hole.
This is because they will compete with each other in finding a watering hole, thus a competitive relationship.

The definition of competition is: two organisms competing for a limited resource.
In other words, they need the same thing, but they need to compete to get it, as there is a limited amount of it in the world. 
Because of this, the answer is D. 

A is called Mutualism,
B is called Parasitism,
C is called Commenalism 
D is called Competition 
:)