Statement – I: When photons of frequency  $4.3\times {10}^{15}Hz$ is incident on the surface of threshold frequency $5\times {10}^{15}Hz$  then no photoelectron emitted from the surface. 
Statement – II: Number of electrons ejected depends on intensity 

Statement-I  is True, Statement-II  is True ; Statement-II  is NOT a correct explanation for Statement-I

Statement- I  is True,  Statement- II  is True ; Statement- II  is a correct explanation for Statement- I

Statement- I is True, Statement- II  is False.

Statement- I  is False, Statement- II  is True.