Choose the correct answer: A, B or C.

1 It's the worst hotel I ….. at and the first I ….. about. A have stayed, have complained B have stayed, complained C stayed, complained
2 We ……. to reach the summit, but Tom ….. ill at the base camp. A had planned, had fallen B had been planning, fell C had planned, fell
3 Where…..? I ….. you all morning! A were you, have called B have you been, have been calling C have you been, have called
4 The city …… much more polluted than I ….. A was, have expected B was, had expected C had been, expected
5 We……to contact Tom three times already, and he still……. A have been trying, hasn't responded B have tried, hasn't been responding C have tried, hasn't responded