Answer:
B. Dynamite exploding
Step-by-step explanation:
A large K implies that most of the reactants are converted to products at equilibrium. It implies that the reaction mostly proceed to the right with a substantial amount of product at equilibrium. Hence the reaction tends towards the right-hand side.
Dynamite exploding is a combustion reaction. Remember that a combustion reaction will have a larger value of K than all other processes listed in the question.