Step 1: Understanding the Concept
Molecularity applies to an elementary step and equals the number of species that collide to react.
Step 2: Count
In \(\text{A}+\text{B}\rightarrow\) products, one A and one B take part.
Step 3: Conclusion
The reaction is bimolecular, so its molecularity is 2.
Final Answer:
The molecularity of the reaction is 2.
\[ \boxed{\text{(C) }2} \]