Which of these represent time averaging?

• A. ( frac{1}{V} int_V phi dV )
• B. (lim_{V } frac{ u20611}{V} int_V phi dV )
• C. ( frac{1}{T} int_t^{t+T} phi dt )
• D. (lim_{T } u2061 frac{1}{T} int_t^{t+T} phi dt )