Which expression has a value of 15, using only four 4s and any of the following: + , – , · , ÷, exponents, and/or parentheses? A. 44 – (4 ÷ 4) B. (4 · 4) – (4 + 4) C. (4 · 4) – (4 ÷ 4) D. (4 + 4 + 4) ÷ 4