Dear aspirant!

Hope you are doing great! If you want to appear for the NDA exam so you must not depend on a particular book as it is all indian exam.So competition is tough in this.So it is not appropriate to suggest you a particular book.However for your help I can suggest you some books for better preparation of GAT section. Here it is pathfinder,arihant mock test ,arihant solved papers,25 mock test by team arpit(online available)

Hope this helps!

Thanking you