HELP (SEE IMAGE) what triangle must be a right triangle and why???

Answer:
D. [tex]\triangle BGC[/tex] is right angle because [tex]$\overleftrightarrow{EG}$[/tex]⊥ [tex]$\overline{CC'}$[/tex]CC'.
Step-by-step explanation:
Given A figure in which line EG is perpendicular to Segment CC'
Therfore ,[tex]\triangle BGC[/tex] is a right angled triangle because in which [tex]\angle BGC=90^{\circ}[/tex]
A right angled triangle is that type of triangle in which one angle is of 90 degree .Then ,we say the the triangle is a right angled triangle.
Now , we can see from the given figure in [tex]\triangle BGC[/tex] line EG is perpendicular is given . Hence, we are given
[tex]$\overleftrightarrow{EG}$[/tex][tex]\perp[/tex][tex]$\overline {CC}'$[/tex]
[tex]\therefore[/tex] , [tex]\angle BGC=90^{\circ}[/tex]
Hence, we can say the triangle BGC is a right triangle.
Now, we check given option
A. It is false. Because no information about the triangle A'B'C' .In given statement the triangle A'B'C' is the reflect image of the triangle ABC .So we can not say [tex]\triangle A'B'C'[/tex] is a right angle .
B. ADC is a right triangle because [tex]$\overline{AA'}[/tex] intersect AC at C.
It is false.Because we can see from given the figure AC not meet in given figure.
C. [tex]\triangle BCC'[/tex] is a right triangel because B lies of the reflection .It is false.Because we can't say that BCC' is a right angle if B lies of the reflection.
D. [tex]\triangle BGC[/tex] is a right triangle because [tex]$\overleftrightarrow{EG}[/tex][tex]\perp[/tex][tex]$\overline{CC'}[/tex]
It is true. Because EG is perpendicular it means [tex]\angle BGC=90^{\circ}[/tex]. Hence, we can say triangle BGC is right triangle.