Statement-I : Y-X graph of a transverse wave on a string is as shown in the figure.  At the given instant, point P is moving downwards.  Hence, we can say that wave is moving along +x direction.
 

Statement-II : Particle velocity is $V_P=-V\left(slope\right).$

Statement-II is correct but Statement-I is incorrect

Both Statement-I and Statement-II are correct but Statement-II is not the correct explanation of Statement-I

Both Statement-I and Statement-II are correct and Statement-II is the correct explanation of Statement-I

Statement-I is correct but Statement-II is incorrect