The correct Active/Passive form of the given sentence is:

☀ I was most rudely answered in the shop.

Explanation for other options:

☀ I have been most rudely answered in the shop. This option uses the present perfect tense ("have been most rudely answered"), which suggests an action that started in the past and has ongoing relevance to the present. The original sentence is in the simple past tense, so the correct form should be "I was most rudely answered in the shop."

☀ I had been most rudely answering in the shop. This option uses the past perfect continuous tense ("had been most rudely answering"), which is not appropriate in this context. The correct form should use the passive voice, not the continuous tense. The correct form should be "I was most rudely answered in the shop."

☀ I were most rudely answered in the shop. This option uses "were," which is the incorrect verb form for the first-person singular pronoun "I." The correct form for the singular subject "I" is "was." The correct form should be "I was most rudely answered in the shop."