By definition, the perimeter of the triangle is the sum of its sides.
We must then use the formula of distance between points:

We now look for the longitus for each of the sides:
For L1:

For L2:

For L3:
Then, the perimeter is given by:
P = L1 + L2 + L3
Substituting values we have:
Answer:
the perimeter of triangle ABC is:
none of the above.