In this task, you're given a passage, further information available on a particular linked term from the statement, and an answer term. Your job is to generate a question that can use the information provided to obtain the given answer. You should use the information on both passage and link information to create the question. Note that the answer to the question should be exactly the given answer, and if the answer is none, the answer to the question shouldn't be obtainable from the passage or linked information.

Passage: From 1966 to 1968, he starred in the BBC radio comedy The Embassy Lark, a spin-off of The Navy Lark. He appeared in at least one episode of The Navy Lark as CPO Nathanial Pertwee, filling in for Jon Pertwee who was indisposed. He also appeared in at least one episode of The Navy Lark as his character from The Embassy Lark. In 1969, he starred in The Big Business Lark which ran for one season of thirteen episodes. This was not strictly a spin-off from The Navy Lark, other than being another "Lark" written by Laurie Wyman. He continued to appear in films, mostly comedies, during the 1960s and 1970s, including Carry On Screaming!, alongside Steptoe and Son star Harry H. Corbett, The Early Bird, The Big Job, The Bed Sitting Room, Up the Chastity Belt, Some Will, Some Won't, "A Funny Thing Happened on the Way to the Forum" and No Sex Please, We're British, as well as television sitcom spin-offs. He appeared in The Private Life of Sherlock Holmes (1970) as the one-armed doorman for the Diogenes Club. In 1974, he made a rare dramatic appearance as Prince Albert in the second episode of Fall of Eagles.
Link Information: none Answer: none
Which of the films Thornton appeared in in the 1960s and the 1970s had the largest box office gross?