What word fits the following definition: inventing fictitious circumstances to avoid undesirable responsibilities
there are no multiple choice.

The word should be Lying. When you don't want to have undesirable responses or suffer undesirable consequences, you lie, that is, you invent fictitious circumstances. Example would be someone asks you do to something and you invent that you have something else planned even if you don't have anything planned.

Attached.

Explanation:

Connotation can shift somewhat based on personal perception and experience—you'll usually manage well enough if you just respond to how the word makes you feel.