Question 14 (1 point) Which of the following represents a possible equation for a sinusoidal function with an amplitude of 4 and a period of x? O a) f(x) =4cos[2(x- x)] +5 Ob) f(x)=2cos 4x -1 Och f ( x ) = 4 sin " ( x- 2* ) +1 O d) All of the above