Answer:
D
Explanation:
A single-replacement reaction occurs when one element replace another in a single compound.
[tex]single replacement = dual replacement = d - 1 replacement = e - d-e = single replacement or 1^2 x^{2} \lim_{n \to \infty} a_n x \left \{ {{d=2} \atop {e=2}} \right.[/tex]