The electron concentration in an n-type semiconductor is the same as hole concentration in a p-type semiconductor. An external field (electric) is applied across each of them. Compare the currents in them. (1) No current will flow in p-type, current will only flow in n-type. (2) current in n-type=current in p-type. (3) current in p-type > current in n-type. (4) current in n-type > current in p-type.
Option 4) The current through a semiconductor is, I=neAvd=neAμE [∵vd=μE] Where, μ is the mobility of charge carriers. ⇒In/Ip=neeAμeE/nheAμhE ⇒In/Ip=μp/μh ∵μe>μh ⇒In>Ip
