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)