Answer: The politicians<u> have been discussing</u> the social program for the last month.
Explanation<u>:</u><u> The present perfect progressive tense</u> is mainly used to refer to an action or event that started in the past and continues in progress at present. This tense<u> is formed with the verb "have" or "has" plus "been" plus the present participle of a verb.</u> Moreover, the present participle of a verb always ends in -ing. In that way,<u> the present perfect progressive form of the verb "discuss" is "have been discussing"</u> ("discussing" is the present participle of "discuss").