Congratulations rats, you all have won again

I just had my mother's nissan micra xtronic CVT wiring repaired recently after rats caused havok in this car which was not a problem in the last (almost) 12 years of owning this vehicle and look at this now. I am genuinely very mad that the precautions of spraying rodent spray and what not did not work. The cats that are there in my apartment are worthless. If anyone can recognise which line is this (under the air filter) in the first picture,, I would be very grateful. Mom is now thinking about just selling off the car.