Answer: The right answer is A time of childhood enjoyments.
Explanation: In this well-known lyric poem by English Romantic poet William Wordsworth (1770-1850), the speaker specifically refers to the butterfly as "historian of my infancy" (third stanza) and he recalls the "pleasant days," "the sweet childish days," when he and his sister tried to chase her, so it is possible to assert that seeing the butterfly brings a time of childhood enjoyments to the speaker's mind, and that is why he asks her to stay near him and to come often to them.
