Notice that for option B
f< 6 means that all numbers less than 6 are solution to the inequality, also notice that -1,1,3 and 4 are less than 6.
An analogous reasoning apllies for option E, all numbers less than 5 are solution to the inequality c<5 then -1,1,3 and 4 are solution.
For the rest of the inequalities at least one of the provided numbers are no solution for the inequality.
