Answer:
f(x) = -x -1
Explanation:
You can make the correct choice by seeing which equation works for the first line of the table.
f(-1) = -(-1) -1 = 0 . . . . . the first equation works
f(-1) = -(-1) +1 = 2 . . . not zero
f(-1) = -1 -1 = -2 . . . not zero
f(-1) = 1 -(-1) = 2 . . . not zero (same as second equation)