● 2010: International Team of Astronomers confirmed Albert Einstein's theory of general relativity and that the expansion of the universe is accelerating after looking at data from the Hubble Space Telescope. There is an unknown source of energy in the universe which is causing the cosmic expansion to speed up. 2016 : Japanese researchers' study finds that the expansion of the universe could be explained by a cosmological constant, as proposed by Einstein in his theory of general relativity. So second statement is right. This eliminates B and (C) ● 2018: Hubble Space Telescope captured image of a phenomenon called Einstein Ring. Einstein in his theory of general relativity, had suggested that a massive object would warp space and time. So, statement 3 is right. Hence we are left with correct answer "D": 1,2 and 3 all correct. [Ref: TheHindu Newspaper]