The following data give the dates of successive turning points in economic activity and the corresponding levels of real GDP at the time. Turning Point Date Real GDP (1996 $ billions) July 1953 1992.2 May 1954 1941.0 Apr. 1957 2182.7 Apr. 1958 2117.4 Apr. 1960 2391.0 The following data give the dates of successive turning points in economic activity and the corresponding levels of real GDP at the time. Which of the following periods is an expansion? Select one: a. May 1954 through April 1958 O b. July 1953 through April 1957 C. May 1954 through April 1957 O d. July 1953 through May 1954 Clear my choice