Answer:
D. 1
Step-by-step explanation:
The amplitude of a periodic function is given by:
[tex]amplitude = \frac{ |max - min| }{2} [/tex]
The minimum value from the graph of the function is -1 and the maximum value is 1.
Therefore the amplitude of the function is:
[tex] = \frac{ |1 - - 1| }{2} = \frac{ |2| }{2} = \frac{2}{2} = 1[/tex]
The correct answer is option D.
