Plz asap (geometry) simmilar triangles

The correct option is (A) DEF

Explanation:
For similarity, one triangle has to be at least the scaled version of another. In the triangles given above as you can see:

The length of DE ( in DEF) = 5.5
The length of AB (in ABC) = 11 which is 2*(The length of DE ( in DEF))

Likewise
The length of EF( in DEF) =  2.5
The length of BC(in ABC) = 5 which is 2*(The length of EF ( in DEF))

Same goes for the third side. 
Hence the correct option is (A) DEF