An insurance policy premium of $1,200 was paid on September 1, 2012, to cover a one-year period from that date. An asset was debited on that date. Adjusting entries are prepared once a year, at year end. The necessary adjusting entry at the company's year-end, December 31, 2012, is:

A. Prepaid Insurance $400
Insurance Expense $400
B. Insurance Expense $800
Prepaid Insurance $800
C. Prepaid Insurance $800
Insurance Expense $800
D. Insurance Expense $400
Prepaid Insurance $400