Spores in the air or contamination through some sort of insect interaction. In an open system, there are billions of microbial agents floating around. With an open container containing a food source and time, the likelihood of contamination is nearly %100.
I believe the correct answer is B
Law of Action and Reaction mean "To every action there is equal and opposite reaction.
Explanation:
It is Newtons third law which explained few things such as :-
1. The nature of the forces between the two interacting objects.
2. According to this law , the force that is exerted from Object-1 to Object-2 is said to be equal in magnitude and opposite to the direction to the force exerted to object 2 upon object 1.
3. Eaxmple - As we push against the wall - Action , the wall in return opposes equal force to resist the pressure of the hand - Reaction.
