Topic: Idioms & Phrases,

Best Answer Explained in Below-:

The phrase "at a stretch" commonly refers to doing something continuously or for an extended period without interruption. When evaluating the options given, it becomes clear that "without break/without stopping" precisely encapsulates this meaning.

In contrast, option A, "irregularly," suggests a lack of consistency, which directly contradicts the notion of doing something "at a stretch." Option C, "decaying," implies a gradual decline or deterioration, which is unrelated to the concept at hand. Option D, "long way," might suggest a distance but does not convey the idea of continuity or persistence.

The essence of "at a stretch" is about maintaining an activity or effort over a period, emphasizing endurance and focus. Therefore, the best choice is option B, as it captures the uninterrupted nature of an action performed "at a stretch," allowing for a clear understanding of the phrase in various contexts, such as studying for exams or completing work assignments.