The action by Y Corp. is best described as a C. Self-tender strategy.
A self-tender is a defense strategy that thwarts a hostile corporate takeover.
Using a self-tender strategy as described in this scenario involves Y Corp. making a tender offer for its shares, inviting its shareholders to sell their shares so that the company can repurchase them at a specified favorable price.
This self-tender strategy closes off X Corp's efforts to succeed with the hostile tender offer.
Thus, the action by Y Corp. is best described as a C. Self-tender strategy.
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