Final answer:
The group most likely to target only the House of Representatives is the one wishing to have a new subcommittee created to limit the sale of over the counter decongestants.
Step-by-step explanation:
The group that is most likely to target only the House of Representatives is the group wishing to have a new subcommittee created to limit the sale of over the counter decongestants. Interest groups often target lawmakers they think will consider introducing or sponsoring specific legislation.
In this case, the group is seeking to create a new subcommittee, which falls under the jurisdiction of the House of Representatives. By focusing on the House, they can direct their efforts towards lawmakers who are more likely to be receptive to their cause.