Why does Fourier series not apply to the function rect((t)/(T))? Find the Fourier Transform of the single sine pulse x(t) defined as x(t)={(sin(2pi f_(0)t),-T<=t<=T),(0, else):}

Options:
a. Because the function rect((t)/(T)) is not periodic
b. Because the function rect((t)/(T)) is a non-linear function
c. Because the function rect((t)/(T)) is not continuous
d. Because the function rect((t)/(T)) is not piecewise smooth