You will be given a definition of a task first, then some input of the task.
In this task, you're given a question, a context passage, and four options which are terms from the passage. After reading a passage, you will get a brief understanding of the terms. Your job is to determine by searching and reading further information of which term you can answer the question. Indicate your choice as 'a', 'b', 'c', or 'd'. If you think more than one option is plausible, choose the more probable option to help you answer the question.

Question: What countries border the sea where the German torpedo boat T7 laid minefields? Passage:The German torpedo boat T7 was one of a dozen Type 35 torpedo boats built for the Kriegsmarine (German Navy) during the late 1930s. Completed in 1939, she was not combat ready until mid-1940 when she spent several months escorting minelayers as they laid minefields in the North Sea and the English Channel. The boat participated in an abortive attempt to attack several convoys off the Scottish coast in November. T7 returned to Germany for a refit in January 1941 and then supported operations in the Baltic Sea after the start of Operation Barbarossa in June. The boat was one of the escorts for several commerce raiders passing through the English Channel in late 1941 and then escorted German ships in Norwegian waters in mid-1942. She was briefly placed in reserve later that year and was then reactivated for service with the Torpedo School. T7 was sunk in an air raid in July 1944, but was refloated several months later. She was never repaired and was scrapped in 19471949.
Links: a. North Sea b. Kriegsmarine c. North Sea d. Reserve fleet
Output:
a