Which of the following will be the SIXTH sentence after rearrangement?

(a) is the right answer. PSRTUQ is the correct order. P begins the passage by establishing the subject- A photo taken in Greenland, which shows sled dogs in ankle-deep water. It highlights the impact of climate change. S follows P. It takes the discussion forward. It talks about the source of water- a 1.2 metres thick ice sheet. R follows S. It talks about the view of the scientists regarding the melting of ice in Greenland. It shows the concern of the scientists. T follows R. It talks about another event that reinforces the concern shown by the scientists- the premature melting of Arctic permafrost. U follows T. It talks about what these events indicate about the state of the world's climate. Q ends the paragraph. It ends the passage by highlighting that climate change is happening at an unprecedented rate.