Among those options, choice c would typically not be classified as a current liability:
c. A long-term noté payable maturing within the coming year
The other options represent obligations that are due within a relatively short time period (within the year), so they would qualify as current liabilities:
a. A six-month bank loan to be paid with the proceeds from the sale of common stock. (Maturing within 6 months)
b. Rent revenue received in advance. (Presumably due within the year)
d. Estimated liability from cash rebate program (Would come due within the year)
So the key is that choice c represents a long-term note payable that just happens to mature within the coming year. But conceptually, it is still considered a long-term liability.
Does this help explain the reasoning? Let me know if you have any other questions!