Answer:
Point of trough = B and D
Step-by-step explanation:
As per the data given in the question,
The troughs are those points where the real GDP of economy fails and then later it increases. In July 1953 real GDP is 1992.2, which further fails to 1941 in May 1954, and then increases again to 2182.7 in April 1957. Hence B is that point where trough takes place.
Likewise, Real GDP is falling to 2,117.4 in April 1958, which Rising to 2391.0 in April 1960. Therefore D is also that point where trough takes place.
Thus, Option (e) : point (B) and (D) is correct answer.