The correct answer is: A. have been launched.
The verb “launch” is transitive, which means it requires a direct object. In this case, the direct object is “new series.” The past participle “launched” is used to form the perfect tenses, which are used to describe actions that have been completed or that happened before a certain point in time. In this case, the action of launching the new series has been completed, so the perfect tense is used.
The other options are incorrect because they do not use the correct verb tense. Option B, “launched,” is in the simple past tense, which is used to describe actions that happened at a specific time in the past. Option C, “has been launched,” is in the present perfect tense, which is used to describe actions that have been completed or that happened before a certain point in time. Option D, “are launching,” is in the present progressive tense, which is used to describe actions that are happening now.
In conclusion, the correct answer is: A. have been launched.