The correct option is B it
Impersonal pronouns are used when we want to refer to people in general, to things, unspecified objects or animals. 'It' is the most commonly used impersonal pronoun. There are several situations where we can use 'it'. In this sentence, 'it' is used to refer to a preceding statement, 'Raj walked his way to office everyday'. Hence, Option C is correct since here 'it' is referring to him walking to office everyday. Raj is a proper noun because it is the name of a person. Thereby, Option A is incorrect. 'He' is a pronoun used to refer to a man or boy previously mentioned. Hence, Option B is incorrect. 'His' is used to as a connecting word or to show belonging. Hence, Option D is incorrect.