On October 12, 2010, Neptune Corporation invested $700,000 in short-term available-for-sale marketable securities. The market value of this investment was $730,000 at December 31, 2010, but had slipped to $725,000 by December 31, 2011. Assuming Neptune does not sell this investment, the mark-to-market adjustment necessary at December 31, 2011, includes: A $5,000 debit to Unrealized Holding Gain on Investments. A $25,000 credit to Unrealized Holding Gain on Investments. A $5,000 debit to Investments in Marketable Securities. A $725,000 debit to Investments in Marketable Securities