Adding Fractions Should Be Introduced in Which Order (From Least

Multiple Choice

Adding fractions should be introduced in which order (from least to most complex) ?

A) like denominators, unlike denominators, one denominator that is a multiple of another
B) unlike denominators, one denominator that is a multiple of another, like denominators
C) like denominators, one denominator that is a multiple of another, unlike denominators
D) unlike denominators, like denominators, one denominator that is a multiple of another