Max was holding a pistol in his hand.

Explanation:
Max was holding a pistol in his hand. A pistol is a handheld firearm designed to be held and fired with one hand. It typically has a short barrel and is used for self-defense or as a weapon in combat.

Reasoning:
To determine the answer, we need to analyze the given options and consider the context provided in the question.

Analysis of options:
a) Pistol: A pistol is a type of firearm that is designed to be held and fired with one hand. It is a possible answer based on the question's context.
b) Knife: A knife is a sharp-edged tool or weapon that is typically used for cutting or stabbing. Although it is possible for Max to be holding a knife, the question implies that he is holding a firearm.
c) Stick: A stick is a long, slender piece of wood or other material that is typically used for support or as a weapon. While it is possible for Max to be holding a stick, the question suggests that he is holding a weapon that is more lethal.
d) Piece of paper: A piece of paper is a thin, flat material made from cellulose pulp. It is unlikely that Max would be holding a piece of paper in a context that suggests he is armed or in a threatening situation.

Conclusion:
Based on the analysis of the given options and the context provided in the question, the correct answer is option 'A' - a pistol. Max is holding a pistol in his hand.