A man invited his girlfriend and his girlfriend's sister to his flat late at night to use heroin. He supplied them with the heroin and his girlfriend injected herself, but he injected his girlfriend's sister as she was struggling to find a vein. A short time later, both his girlfriend and his girlfriend's sister started to lapse in and out of consciousness. He was concerned about their health, but did not call for medical assistance as he did not want to be arrested for supplying Class A drugs. He put a blanket over them hoping that they would be fine in the morning. Unfortunately, they both died during the night.Can the man be convicted of any involuntary manslaughter offences?

A、He could be found liable of unlawful act manslaughter or gross negligence manslaughter against his girlfriend; and gross negligence manslaughter against his girlfriend's sister. incorrect
B、He could be found liable of gross negligence manslaughter against his girlfriend and her sister. incorrect
C、He could be found liable of unlawful act manslaughter against his girlfriend and gross negligence manslaughter against his girlfriend's sister. incorrect
D、He could be found liable of unlawful act manslaughter or gross negligence manslaughter against his girlfriend and her sister. incorrect
E、He could be found liable of unlawful act manslaughter or gross negligence manslaughter against his girlfriend's sister; and gross negligence manslaughter against his girlfriend. correct