Which statement describes the end behavior of the function f(x)=-3x^2

a sample of water is taken and kept in a beaker in a freezer at a constant temperature of 0°c. if the system is at dynamic equilibrium, which of these statements is true?  

example answer: "to determine if a sum is reasonable you can round each number to the nearest whole and compare the estimated sum to the actual sum."

hope this you and anyone else who needs the answer : ^)