For which acute angle are the sine of the angle and cosine of the angle equal? a. 30º b. 45º c. 60º d. 75º

For this case we have the following definitions:
 
 
 Where,
 x: angle
 C.O: opposite leg
 C.A: adjacent leg
 h: hypotenuse
 Since the hypotenuse is constant, then the angle for which the legs are equal is 45 degrees.
 We have then:
 
 
 B. 45º