Final answer:
The algebraic expression that represents the phrase 'the quotient of -6 and the sum of a and b' is -6 / (a + b), which corresponds to option A.
Step-by-step explanation:
The phrase 'the quotient of -6 and the sum of a and b' can be translated into an algebraic expression by first identifying the operation involved. 'Quotient' indicates division, and 'the sum of a and b' tells us we are adding a and b together. Therefore, the algebraic expression for this phrase is -6 / (a + b). This means option A is correct. Simplification is not possible in this case, as we need specific values for a and b to proceed further.