Using flattened data, you may wish to create a flag on the Most Recent Responses per Participant. With this two variable system, this result can be achieved.
1. Create your variables
Variable 1: Most Recent Response
Returns the most recent Response ID per Participant
= Max([Response ID_####]) In ([Participant Site Identifier])
Variable 2: Flag for Response
Flags the most recent response ID based on which response ID is equal to the maximum response ID per participant
= (If [Response ID_###] = [Most Recent Response] Then 1 In([Participant Site Identifier];[Response ID_####];[Date Taken_####])) In ([Participant Site Identifier])

2. Filter on the Flag
Bring the flag in to the table
Right click the column
Filter > Add Filter
Set Flag for Response Equal to 1


You will then see one row of the objects attached to the most recent response for each participant.

This can also be achieved on an individual question basis with this article.