Answer and Explanation:
The heuristic device here is confirmation bias. Confirmation bias occurs when we confirm previous beliefs by seeking out evidence albeit in an impartial manner such that we do not look or consider all the facts. This is demonstrated by agartha as she only cuts out the area where there is g*n violence or harmful use of guns buy doesn't consider all facts to the problem such as the other places where g*ns could actually be live savers. She could avoid this by trying to broaden her perspective or considering all the facts