1. An exponential function is shown below. f (x)= -2(2)
Which key attribute does the function not exhibit?

This question seems extremely odd to me. I don't really even understand what's being asked.

As far as exponential functions go, it's missing an exponent for one. The dependent variable is missing. This essentially saying f(x) = -4 or y = -4. Which is fine, but is definitely not an exponential function and in a very odd and incomplete form to begin with.