Given that: y=Asin⁡2πλ(ct−x), where y and x are measured in the unit of length. Which of the following statements is true?

Here units of y and A will be same and that of x and λ will be same 2πλ(ct−x) is dimensionless. Here ct/λ and x/λ are dimensionless. Unit of ct is same as that of λ or x.