两位数的十位数字与个位数字之和为$$12$$，  而数字均为$$0\sim 9$$，故枚举得：  $$93$$，$$84$$，$$75$$，$$66$$，$$57$$，$$48$$，$$39$$共$$7$$个．  故选：$$\text{C}$$． 
2019年第$$24$$届$$YMO$$一年级竞赛决赛第$$6$$题$$3$$分  The sum of the ten digits and the single digit is $$12$$, and there are a total of  such two-digit numbers.  十位数字和个位数字相加的和是$$12$$，这样的两位数一共有个． 

[a] $$5$$ 
[b] $$6$$ 
[c] $$7$$ 
[d] $$8$$ 