Stocks got hammered Monday as big sellers again made their presence felt. The Nasdaq slumped 3%, closing near its session low. It’s getting close to the 4500 level, which it has stayed above on a closing basis since late October. Health care stocks, which make up about 16% of the Nasdaq composite, again came under heavy fire. IBD’s biotech industry group tumbled 7.6% after plummeting 15% last week.