Hydrogen is an element _____ atomic number is 1 and _____
  atomic weight is 1.008.
  A) whose / whose
  B) of which / whose
  C) which / of which
  D) which / which

   The accident was seen by some people _____ at a bus stop.
   A) waited
   B) waiting
   C) were waiting
   D) who waiting

  Who is that pretty girl _____ ?
  A) that everybody is looking
  B) everybody is looking at her
  C) which everybody is looking
  D) everybody is looking at

  Those are the kids _____ rescued my kitten.
   A) who
   B) which
   C) whose

  Crops can now be grown in deserts _____ .
  A) most of them are in Africa
  B) it was impossible to cultivate the land
  C) where farming would be impossible without irrigation
  D) these are known as dry areas

  The man _____ you met at the party was a famous film star.
  A) who
  B) when
  C) where
  D) which

  _____ I am talking about does not really concern you.
  A) What
  B) That's what
  C) Why
  D) It's why

  At first, I couldn't tell _____ he was, but then I recognized him.
   A) who
   B) which
   C) whose

  My doctor, from _____ I have few secrets, is a close friend of mine.
  A)_____
  B) who
  C) that
  D) whom

  The young sociologist _____ article
  was published in the "National
  Geographic" had travelled 1700 miles
  across Australia's western wilderness.
  A) whose
  B) who
  C) that
  D) which
  E) whom