Match electrical properties listed in Column - II with materials listed in Column - I.
`{:("COLUMN - I","COLUMN - II"),("A) Pure crystal of silicon at 0 K","p) Semi conductor - p - holes carry current"), ("B) Pure crystal of silicon at 400K","r) Semi conductor - electrons carry current"),("C) Silicon crystal doped with arsenic impurity","r) Insulator"),("D) Silicon crystal dopped with gallium","s) Semi conductor - equal number of p - holes and electrons carry current"):}`

Answer

`A-r; B-s; C-q; D-p`

Explanation

At OK pure silicon acts as insulator At 400 K pure silicon acts as semiconductor, equal no of P-holes and electrons carry current Si doped with As - semiconductor - electrons carry currant Cn type).
Si doped with ‘Ga’ - semicondcutor P-holes carry current (P-type)