1) The two years between which the rate of change of cellular phones is minimum are : A) 1997 and 1998 B) 1999 and 2000 C) Both A and B D) 2001 and 2002 Answer: Option CExplanation:In 1997 and 1998, difference =40000-48000=-8000 In 1999 and 2000 difference= 25000-30000=-5000 In 2001 and 2002 difference = 40000 - 18000= 30000 The minimum in 1997 and 1998 ,1999 and 2000