Erascible Company has $13,000 in cash, $7,000 in marketable securities, $27,000 in accounts receivable, $20,000 in inventories, and $30,000 in current liabilities. The company's current assets consist of cash, marketable securities, accounts receivable, and inventory. The company's acid-test ratio is closest to:

a) 1.57

b) 0.90

c) 1.33

d) 2.23