Syllabus Reference: 1.2.3 — Errors, defects, failures, and root causes

Source: ISTQB CTFL v4.0 Sample Exam A, Question #A3

A phone ringing in a neighboring cubicle distracts a programmer causing him to improperly program the logic that checks the upper boundary of an input variable. Later, during system testing, a tester notices that this input field accepts invalid input values.

Which of the following correctly describes an incorrectly coded upper bound?