The Fourier transform of f(t) = cos ω₀t is

• A. π[δω₀ + δ(- ω₀)]
• B. π[δ(ω - ω₀) + δ(ω + ω₀)]
• C. π[δω₀ - δ(- ω₀)]
• D. π[δ(ω - ω₀) - δ(ω + ω₀)]