A 2-column table has 5 rows. The first column is labeled x with entries negative 2, negative 1, 0, 1, 2. The second column is labeled f (x) with entries 0.2, 0.4, 0.8, 1.6, 3.2.
Which exponential function is represented by the table?

f(x) = 2(2x)
f(x) = 0.8(0.8x)
f(x) = 2(0.8x)
f(x) = 0.8(2x)