(a) (Eg)Si < (Eg)Ge  < (Eg)C
(b) (Eg)C < (Eg)Ge > (Eg)Si
(c) (Eg)C > (Eg)Si > (Eg)Ge
(d) (Eg)C = (Eg)Si = (Eg)Ge
14 4
In an unbiased p-n junction, holes diffuse from the p-region to
n-region because
(a) free electrons in the n-region attract them (b) they move across the junction by the potential difference (c) hole concentration in p-region is more as compared to n-region