Which statement correctly compares the Sec system and the Tat system?

a. The protein SecA delivers cytoplasmic proteins to either the SecYEG channel or the TatABC channel
b. Proteins that have co - factors cannot be translocated by the Tat system
c. Both are forms of active transport, requiring energy for transport to occur
d. While the Sec system depends on a signal peptide, proteins that are translocated by the Tat system do not need signal peptides