Big Corp is a defendant in a disparate treatment case brought by Pam who is charging that she was denied a promotion because of gender discrimination. Big Corp will likely win if it can establish as a defense that

d. Either A or C

Explanation:

Based on the information provided within the question it can be said that Big Corp will likely win if it can establish as a defense that either Pam was denied the promotion for legitimate non-discriminatory reasons or the denial of the promotion was based on mixed motives. Any of these two defenses would tell the court that there were other reasons as to why Pam was denied the promotion and it is not due to gender, which would make Pam's argument invalid.