A is accused of the murder of
B.At his trial .Which of the following fact/facts may be in issue?

"Facts in issue".-The expression "facts in issue" means and includes--any fact from which, either by itself or in connection with other facts, the existence, nonexistence, nature or extent of any right, liability, or disability asserted or denied in any suit or proceeding, necessarily follows. A is accused of the murder of B. At his trial the following facts may be in issue:-- That A caused B's death; That A intended to cause B's death; That A had received grave and sudden provocation from B; That A at the time of doing the act which caused B's death, was, by reason of unsoundness of mind incapable of knowing its nature.