Three copies of a triangle were rotated and positioned as shown. which statement is always true about the angles in the figure?
a. angle a and angle b form a right angle
b. angle a, angle b, and angle c, form a straight angle.
c. angle a, angle b, and angle c from a acute angle.
d. angle a and angle c form a right angle

If the above image is the supposed image for this problem, then,

B. Angle A, Angle B, and Angle C, form a straight angle.

A straight angle is 180°. C A B found in the middle of the picture forms the 180° straight angle.

Right angle is an angle which is equivalent to 90°
Acute angle is an angle which has less than 90°

As I can observe, the three triangles have two equal sides and two equal angles. These triangles are identified as isosceles triangles.