Taxpayer A leases a building for 15 years. Taxpayer B secures the right to lease a building for 15 years by signing a three-year lease with two renewable option periods—one for 2 additional years and a second for 10 years. Both A and B incur leasehold improvement costs at the beginning of the lease. Explain the tax treatment of the leasehold improvements to both A and B. Which taxpayer has signed the better lease? Explain.