What is a placement group?
A.
A collection of Auto Scaling groups in the same region
B.
A feature that enables EC2 instances to interact with each other via high bandwidth, low latency
connections
C.
A collection of authorized CloudFront edge locations for a distribution
D.
A collection of Elastic Load Balancers in the same Region or Availability Zone
Explanation:
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/placement- groups.html
B, A feature that enables EC2 instances to interact with each other via high bandwidth, low latency connections
http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/placement-groups.html
A placement group is a logical grouping of instances within a single Availability Zone. Placement groups are recommended for applications that benefit from low network latency, high network throughput, or both. To provide the lowest latency, and the highest packet-per-second network performance for your placement group, choose an instance type that supports enhanced networking. For more information, see Enhanced Networking.