Questions

'an' at the end of the first fixed segment indicates that Q, R and S can't follow the first segment. This leaves us with only one choice i.e. P. This eliminates options 2, 4, and 5.

There are only two such options: option A1and 3. Option 3 can be eliminated since part S ends with 'the' which can't be used as the end of the master statement. Hence, the correct sequence is PRSQ

India   signed   a   historic   deal   to develop    the    strategic    port    of Chabahar  in  Iran  and  agreed  on  a three-nation    pact    to    build    a transport-and-trade corridor through   Afghanistan   that   could help  halve  the  time  and  cost  of doing  business  with  Central  Asia and     Europe.     Developing     the  Chabahar  port  was  seen  as  crucial for  India  because  it  will  not  only allow New Delhi to bypass Pakistan and access global markets but also counter    China’s    expanding influence   in   the   Indian   Ocean region. But the project’s land route through   Afghanistan   remains   a security headache

AIDS is caused by the Human Immuno deficiency Virus (HIV), a member of a group of viruses called retrovirus, which have an envelope enclosing the RNA genome. Transmission of HIV-infection generally occurs by (a) sexual contact with infected person, (b) by transfusion of contaminated blood and blood products, (c) by sharing infected needles as in the case of intravenous drug abusers and (d) from infected mother to her child through placenta.