Select the counterexample that makes this conjecture false:
for any real number x, if x2 ≥1, then x ≥1
a. x=1
b. x=1/4
c. x=2
d. x=-3

To answer this problem, we can directly substitute the following options to the given inequalities and check whether each of them makes the inequalities true or false. In this case, option B is only the option which makes the inequalities false since 1/16 is not greater than or equal to 1 and 1/4 is not greater than or equal to 1