1. The problem states: If $m\angle A = m\angle B$ and $m\angle B = m\angle C$, then $m\angle A = m\angle C$. What algebraic property justifies this step? 2. The property used here is the Transitive Property of Equality, which states: If $a = b$ and $b = c$, then $a = c$. 3. This property allows us to deduce equality between $m\angle A$ and $m\angle C$ because they are both equal to $m\angle B$. 4. Reflexive Property means $a = a$, Symmetric Property means if $a = b$ then $b = a$, and Distributive Property relates to multiplication over addition, so they do not apply here. 5. Therefore, the correct answer is the Transitive Property of Equality.