Here is a quote that reads,

*"Students who do not demonstrate proficiency in addition and subtraction math facts with sums up to 10 by the end of the school year will be recommended for retention."*

Does the statement above mean:

(a) To get promoted, the student must pass addition facts with sums up to 10?

(b) To get promoted, the student must pass addition facts with sums up to 10 and subtraction facts with differences up to 10?

I choose choice (a) because the statement explicitly states only "the sums up to 10". The word "sum" is associated with only addition. What do you think? Any suggestions will help. Thanks in advance.