A special power delegated only to the House of Representatives is:

Responses

ratifying treaties with foreign nations
ratifying treaties with foreign nations

proposing a constitutional amendment
proposing a constitutional amendment

bringing charges of impeachment
bringing charges of impeachment

approving presidential appointments

None of the options listed is a power delegated only to the House of Representatives. All of them are powers shared with the Senate or the executive branch. However, one power that is delegated only to the House of Representatives is the power to introduce revenue or appropriations bills (Article I, Section 7 of the Constitution).