What is the general electronic configuration of the lanthanides?

• A. (n-2)f 1-14 (n-1)d 1-10 ns2
• B. (n-2)f 1-14 (n-1)d 1-2 ns2
• C. (n-2)f 1-14 (n-1)d 0-1 ns2
• D. (n-2)f 1-14 (n-1)d 0 ns2