The correct option to fill in the gap in the sentence “Legislators must be trained to … the truth” is B. discern. So, the completed sentence is: “Legislators must be trained to discern the truth.”

Here’s why:

• A. disguise: This option is incorrect because “disguise” means to conceal or hide. Legislators should not be trained to hide the truth.

• B. discern: This is the correct option. “Discern” means to recognize or perceive. Legislators should be trained to recognize or perceive the truth.

• C. digest: This option is incorrect because “digest” means to understand or absorb information, and while it’s important for legislators to understand the truth, it doesn’t fit as well in this context as “discern”.

• D. disturb: This option is incorrect because “disturb” means to interrupt or bother. Legislators should not be trained to interrupt or bother the truth.

• E. distort: This option is incorrect because “distort” means to twist or misrepresent. Legislators should not be trained to twist or misrepresent the truth.