Write the expression for the wavefunction of a harmonic wave of amplitude, period, and speed. The wave propagating in the negative x-direction has a value of?
Options:
A. -A sin(2πx/T - ωt)
B. A sin(2πx/T + ωt)
C. -A cos(2πx/T - ωt)
D. A cos(2πx/T + ωt)