Final answer:
The equation that represents a function is 2y = -12.
Step-by-step explanation:
A function is a mathematical relationship between two variables, where each input value (independent variable) corresponds to exactly one output value (dependent variable).
Out of the given options, the equation that represents a function is C. 2y = -12. This equation can also be written as y = -6, where y is the dependent variable and -6 is the constant value.