Among Other Things,people Hold Cash Balances for Which of the Following

Among other things,people hold cash balances for which of the following reasons?
1) to meet unforeseen emergencies
2) to maximize their returns on interest-earning assets
3) to guard against the uncertainty of the timing of receipts and payments

A) 1 only
B) 2 only
C) 3 only
D) 1 and 2
E) 1 and 3