It depends where your interest lies. But if you think according to the placement opportunities, safety, and fire engineering is much more preferred due to the high demand in the industry. The faculty is also well-qualified along with the quality education that the college provides. But safety and fire engineering deal with a lot of safety responsibilities so, if you are opting for this branch be prepared for that.
However, if you don’t want to be confined in one specific area then go for Mechanical. As it is a core branch, you can get many specializations later.
So, choose a branch according to your interest.