A silicon specimen is made into a p - type semiconductor by doping on an average, one indium atom per 5 x ${10}^7$ silicon atoms. If the number density of atoms in the silicon specimen is  5 x ${10}^{28}$ atoms/${\mathrm{m}}^3$, then the number of acceptor atoms in silicon per cubic centimeter will be

• A

  $2.5 \mathrm{x} {10}^{30} \mathrm{atoms} / {\mathrm{cm}}^{3 }$

• B

  $2.5 \mathrm{x} {10}^{35} \mathrm{atoms} / {\mathrm{cm}}^3$

• C

  $1.0 \mathrm{x} {10}^{13} \mathrm{atoms} / {\mathrm{cm}}^3$

• D

  $1.0 \mathrm{x} {10}^{15} \mathrm{atoms} / {\mathrm{cm}}^3$