A. B acted in the exercise of his right of private defence and is, therefore, not liable.
B. B’s right of private defence of property in case of apprehension of theft did not extend to the causing of death but any harm other than death. Therefore, B is not entitled to claim successfully the right of private defence but at the same time he would be entitled to avail the exception (2) to section 300 and would only be liable for committing culpable domicile.
C. Under section 104 of the Penal Code B could cause any harm other than death in defence of his property. Since B has caused death, he would be liable for murder.
D. Since A entered B’s house at dead of night with a view to commit theft, B was entitled to claim the benefit of section 103 of the Penal Code and will not be liable for murder.
✅ The correct answer is option B.