A panda walks into a café. He orders a sandwich, eats it, then draws a gun and fires two shots in the air. “Why?” asks the confused waiter, as the panda makes towards the exit. The panda produces a badly punctuated wildlife manual and tosses it over his shoulder. “I am a panda,” he says, at the door. “Look it up.” The waiter turns to the relevant entry and, sure enough, finds an explanation. “Panda. Large black-and-white bear-like mammal. Native to China. Eats, shoots and leaves.” So, punctuation really does matter, even if it is only occasionally a matter of life and death.
In 2003 Lynne Truss published Eats, Shoots and Leaves: The Zero Tolerance Approach to Punctuation. The book became a runaway success in the U.K., hitting number one on the best-seller lists and prompting extraordinary headlines such as “Grammar Book Tops Bestseller List” (BBC News). This is a book for people who love punctuation and get upset when it is mishandled. The above passage is printed on its back cover. 【題組】50. The words “shoots” and “leaves” whose meaning has changed dramatically in different contexts are the primary source of ____ in the panda joke.
(A) spelling (B) strategy (C) definition (D) humor