US try to solve this QUESTION step-by-step.The first blank requires an ADJECTIVE and 'only' seems to be the correct alternative. 'Even' cannot be used with 'trouble'.So, options 1 and 2 are already rejected.Option 3 gives 'quite' as the alternative and option 4 gives 'too' as the alternative. The latter is definitely more suitable as 'too' is more definitive.NOTE: 'quite a lot' is the correct usage.