Answer:
The first four.
Step-by-step explanation:
There are 3 main postulates. SSS, SAS, and AAS. This simply refers to how we prove a triangle congruent. With SSS, all 3 sides must be congruent (either proven or given). AAS is when you have 2 angles congruent with a side next to one of the angles. NOT IN BETWEEN (there's an image as to what I'm talking about below). Finally, SAS. This is when you have a set of angles congruent with sides on each side congruent as well (look at the first four as an example of this.
Any more specific questions, feel free to ask!
