Which triangles are similar to triangle ABC?

Answer:
DEF
Step-by-step explanation:
DEF is half of ABC, which means they're both similar in some way.
As we can see line DE is half of line AB (DE is 5.5 and AB is 11)
Line DF and Line EF are half of Line AC and Line BC (DF/EF is 4 while AC/BC is 8)