If the operating income is $7,500. The column heading identified as A is: $1,500 U.
Operating income variance can be defined as the actual operating income minus budgeted operating income.
Operating income variance=Actual operating income-Budgeted operating income
When we look at Column A we can see that column A had $1500U (unfavorable) which is the unfavorable variance of contribution margin.
Inconclusion the column heading identified as A is: $1,500 U.
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