Which of the following are the parameters specified in Amazon ECS Service Definition? (Select Three)

Answer options:

A.Cluster
B.Capacity provider strategy
C.Environment Variables
D.Data Volumes
E.Client token

Answer: A, B, E
A service definition defines which task definition to use with your service, how many instantiations of that task to run, and which load balancers (if any) associate with your tasks
Following are some parameters defined in Service Definition.
 
References:
https://docs.aws.amazon.com/AmazonECS/latest/developerguide/service_definition_parameters.html