Final answer:
The given expressions are already in their simplest form. No further simplification can be done since no operation is specified.
Step-by-step explanation:
Given that we have four different expressions A) 2x + 5 B) 3x - 7 C) 4x + 2 D) 5x + 3, there is actually no mathematical operation in the question that allows us to further simplify these expressions. Each of these expressions are already in their simplest form. An algebraic expression is defined as being simplified when it has no like terms and no parentheses. Additional operations such as addition, subtraction or multiplication in the context of these expressions could alter them, but as standalone expressions, they're already simplified.
Learn more about simplifying expressions