Second, Caterpillar caught a downgrade from Goldman Sachs on Wednesday. Citing decreased demand for materials, it cut Caterpillar to 'hold' from 'buy.' The stock lost about 1 percent to $84.12 on the news, even as it was already down about 5 percent for the year and way off its high of $116 a year ago.
Third, ConAgra declined after it reported a 57 percent drop in earnings, hurt by costs related to its acquisition of Ralcorp.
As Cramer sees it, investors who own ConAgra can sell a little to lock-in gains because nobody ever got hurt taking a profit. But there might be some sleepless nights for those who own Caterpillar, he said. Then again, he said the stock could catapult 20-, 30- or 50 percent higher in a single session.
In the end, Cramer said investors need to realize this market is all about risk-reward.
"Right now this market is not giving you the reward you want with ConAgra, but it's giving you too much risk with Caterpillar," he said. "You get CAT lower, though, then, to me, the choice is clear. You can abandon the expensive ConAgra and buy the cheaper CAT."
— Reuters contributed to this report
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