Filtering out old records

Content

hi all,

I am stuck with creating a report based on data on a custom object. The custom object is related to opportunities table where we keep the history every time an opportunity is updated. So, opportunity to custom object is one to many. 

example data in custom object:

opportunity id   | Response  |   ID

1000                    A                   123

1000                   B                    124

1001                   B                    125

1001                   A                    126

1002                   C                    127

I want to see all the opportunities who have latest value of  'Response=A' in the custom object. So from above example, only opportunity with id 1001 should be included in the report because the value of custom object with highest ID (126) related to opportunity