It is easier to remove an electron from sodium than from copper. If  ${\left({\nu }_0\right)}_s$ and ${\left({\nu }_0\right)}_c$are their threshold frequencies respectively. Then

• A

  ${\left({\nu }_0\right)}_s= {\left({\nu }_0\right)}_c$
• B

  ${\left({\nu }_0\right)}_s> {\left({\nu }_o\right)}_c$
• C

  ${\left({\nu }_o\right)}_s<\left({\nu }_0\right)c$
• D

  ${\left({\nu }_0\right)}_s>= {\left({\nu }_0\right)}_c$