Final answer:
Tanya must include $6,000 in taxable income.
Step-by-step explanation:
To calculate the amount Tanya must include in taxable income, we need to add up the value of the benefits she selected. Tanya selected $3,000 for parking, $2,000 for 401(k) contributions, and $1,000 in cash. Therefore, the total amount Tanya must include in taxable income is $3,000 + $2,000 + $1,000 = $6,000.