A travelling wave represented by y=Asin(ωt−kx) is superimposed on another wave represented by y=Asin(ωt+kx). The resultant is
A.A standing wave having nodes atx=(n+1/2)λ/2, where n=0,1,2
B.A wave travelling along +x direction
C./a wavelength travelling along −x direction
D.a standing wave having nodes at x=nλ2, where n=0,1,2