Given the task definition and input, reply with output. In this task, you're given passages that contain mentions of names of people, places, or things. Some of these mentions refer to the same person, place, or thing. Your job is to write questions that evaluate one's understanding of such references. Good questions are expected to link pronouns (she, her, him, his, their, etc.) or other mentions to people, places, or things to which they may refer. Do not ask questions that can be answered correctly without understanding the paragraph or having multiple answers. Avoid questions that do not link phrases referring to the same entity. For each of your questions, the answer should be one or more phrases in the paragraph, and it should be unambiguous.

Passage: In the 1960s, Axelrod worked as a producer and A&R executive for Capitol Records in Los Angeles. During this time, he began to conceive his own musical ideas, involving a fusion of baroque classical sounds, R&B rhythms, and spiritual themes. Challenged by what he described as a "new breed of record buyer ... more sophisticated in his thinking", he was one of several Los Angeles-based musical eccentrics during the late 1960s who wanted to expand on the mid-1960s studio experiments of Brian Wilson and George Martin. His first attempt at this creative vision was composing a religious-themed, psychedelic opera for the Electric Prunes, a local garage rock group. When the band found it too challenging to finish the recording, Axelrod enlisted studio musicians from the Wrecking Crew to complete the album, released as Mass in F Minor in 1968. The recording attracted both controversy and national fame for the producer.After the success of Mass in F Minor, Axelrod was asked by Capitol to record a similar album. He wanted to further capitalize on the experimental climate of popular music and chose to adapt works by English poet William Blake on an album. Blake musical settings were at the height of their popularity among musicians and composers. Numerous serious music composers had set his poems to music since the 1870s, and the practice was eventually adapted in other musical fields during the 20th century, including popular music, musical theatre, and the 1960s folk idiom. Axelrod, a self-professed "Blake freak", had been fascinated by Blake's painting and poetry since his late teens and frequently read the poems as an adult. He conceived Song of Innocence after he had bought an edition of Blake's complete poetry while working in Capitol's art department and considered the concept for a few years before Mass in F Minor. Axelrod was not sociable with colleagues, such as record executives who could have helped him professionally, and felt that he could identify with Blake; he considered the poet "very bad at making new friends".
What is the last name of the person who composed a religious-themed opera?