The best list to describe the food chain in the given ecosystem would be:
fruit trees, monkeys, birds, tigers
This sequence reflects a typical food chain where fruit trees produce fruit that is eaten by monkeys, which can then be preyed upon by birds (although birds may not typically prey on monkeys, they can feed on fruit or insects that are found in trees). Lastly, tigers are apex predators that may prey on monkeys.
If we focus solely on a more traditional herbivore and carnivore perspective, the top option would be fruit trees, monkeys, tigers as monkeys primarily eat fruit from trees while tigers would be at the top of the food chain as predators.