Identify the topic of the following Treasury Regulations, Revenue Rulings or Revenue Procedures:
a. 26 C.F.R. sec. 601.601(d)(2)(iii).
b. Reg. § 301.6333-1
c. 26 CFR Part 514.5
d. Treas. Reg. 1.482-7(b)(1)(iii).
e. 1.956-1T(e)(5).
f. Rev. Proc. 89–14, 1989–1 C.B. 814
g. Rev. Rul. 2015-25, 2015-49 I.R.B. 695