XYZ Development, Inc. leases commercial space to businesses. Most of the leases are long-term, from five to fifteen years in length and have fixed rents. XYZ's contracts contain a clause in which both parties agree to annual adjustments of rent based on tax increases and other operating costs. If the previous year did not see more than a five percent increase in these costs, there is no change in the rent. What is the clause?

A. Allowable Vacancy Rate Clause
B. Escalator Clause
C. Operating Costs Adjustment Clause
D. Periodic Tenancy Clause