For Partnership Tax Years Ending After December 31, 2015, When

For partnership tax years ending after December 31, 2015, when must a partnership file its return?

A) By the 15ᵗʰ day of the 3ʳᵈ month after the partnership's tax year end.
B) By the 5ᵗʰ month after the original due date if an extension is filed.
C) By the 15ᵗʰ day of the 4ᵗʰ month after the partnership's tax year end.
D) By the 15ᵗʰ day of the 3ʳᵈ month after the partnership's tax year end and by the 5ᵗʰ month after the original due date if an extension is filed.
E) By the 5ᵗʰ month after the original due date if an extension is filed and by the 15ᵗʰ day of the 4ᵗʰ month after the partnership's tax year end.