The Allowance for Doubtful Debts Account Has a Balance at the Start

The Allowance for Doubtful Debts account has a balance at the start of the year of $1000.At the end of the year debts of $990,including $90 GST,are to be written off and the Allowance for Doubtful Debts is to be adjusted to 10% of the closing Accounts Receivable balance of $22 000 including $2000 GST) .The amount for Bad and Doubtful Debts appearing in the Income statement for the year will be:

A) $2000
B) $1900
C) $2100
D) $2200